Difference between revisions of "User:Ted"

Latest revision as of 22:38, 14 November 2024

-- 2017-07-21 शुक्रवार --
User Ted's wiki page at Neela Nurseries
musica, संगीत

OVERVIEW

This wiki document a starting point of Ted's notes on Linux use and configuration, Open Source Software and web development.

This local notes page on Neela Nurseries wiki not yet well organized, but here as a quick stash point for holding useful references and a starting point for more complete and formal documentation.

Music notes here ::: NN keywords template ::: Nordic Devzone posts ::: CircuitDojo Forum ::: Untangling complex C declarations

Keywords: Untangling Detangling Untangling C Declarations Nordic Devzone firmware goals

^ Technology and Tools

Quick links to local notes and references:

1	2	3	4
Technical groups	Hardware references	Operating systems	Tools and Toolchains
The Linux Documentation Project Linux kernel dot org Hackaday Circuit Cellar Devzone Oresat notes Embedded Muse . . . need URL true RNG Devzone posts and others	radio basic components integrated circuits amplifiers modules_celulares Microcontrollers dev boards arduino-notes Raspberry Pi notes memory devices LoRa technology firmware programmers Baldengineer dot com JLink debugger notes multi-core RTOS notes	Zephyr Containers and VMs RTOS notes ThreadX notes general RTOS topics	arm-none-eabi-gcc, gcc, make gdb and general debugging ld linker clang openocd pyocd cmake notes west meta-tool west manifest files Segger Nordic version ctags version control

5	6	7	8
Documentation	Programming languages	Programming languages	Data Integrity
NASA Requirements How-To presentation tools Doxygen notes Restructured Text (rst)	assembly C Device Tree and dts Kconfig shell	Ada Rust Inko Python notes Perl	data integrity methods programming constructs

9	10	11	12
Technologies	Local works	Local works	Code Libraries
Cartesiam Cartesiam AI Studio security topics Wireless communications	Zephyr building blocks reference ^^^ NEEDS ORGANIZATION ^^^ Zephyr device drivers, Jared Wolffstudy Zephyr driver demo nRF modem lib study SPI device tree source code RPi Pico SDK studies firmware goals	sample aws_oit study Zephyr RTOS threads In-tree driver ST Micro IIS2DH Zephyr board porting I2C driver notes	Nordic nrf-sdk Zephyr SDK installation notes CMSIS notes libcurl notes MCUXpresso SDK NXP LPC HAL

13	14	15	16
Open software projects	Comms protocols	Encodings	Hardware issues
Apache2 webserver MCUBoot open governance	I2C SPI Sparkfun tutorial SPI AT commands LTE AT command notes MQTT 2/10 intro series MQTT notes notes serial wire debug SWD notes serial bootloading CAN	JSON notes Protobuf Protobuf notes Intel hex format ASCII cbor notes	specific hardware studies Classic video games

17	18	19	20
Local stuff	Academic	Cloud based services	Interesting projects
NN bulletin board Terminology pages TO DO bookmarker	ECE reference materials	Docker Hub site bifravst Amazon S3 versioning AWS notes CLI and character sequences NTP Pool organization	nRF multi-NUS WS2812 Zephyr driver Eseye IoT telem STM32

^ temporary section

Note: useful to add ratings of completeness and organization to above links that point to local wiki pages.

https://devzone.nordicsemi.com/nordic/cellular-iot-guides/b/software-and-protocols/posts/connecting-to-aws-cloud-services-using-the-nrf9160

https://community.helium.com/t/new-to-helium-start-here/80

http://iotfactory.eu/lorawan-world-frequency-map-lora-sigfox-nbiot-telecom-operators-per-country/ LoRaWAN world frequency map (not exhaustive)

Always useful to review, wiki table syntax help:

 *  wiki table help

Wiki-driven table of contents here:

1 OVERVIEW
2 ^ Technology and Tools
3 ^ temporary section
- 3.1 ↑ ↓ Countries and politics
4 ↑ ↓ Community, Culture, the World
- 4.1 ↑ ↓ Geography and Place
- 4.2 ↑ ↓ People
- 4.3 ↑ ↓ Human languages
- 4.4 ↑ ↓ Science
5 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
6 ↑ ↓ GNU Make and GCC Tools
7 ↑ ↓ OpenOCD and Eagle set up notes
8 ↑ ↓ Mediawiki Issues and Notes
- 8.1 ^ File uploads
- 8.2 ^ Images in wiki pages and image attributes
- 8.3 ^ Mediawiki layout topics like multi column layout
- 8.4 ^ Other Mediawiki topics
9 ↑ ↓ Web Site Building Blocks - Summer 2017 to 2020 Q1 Work
10 ↑ ↓ Open Source License Types
11 ↑ ↓ Linux Packages (Separate Article)
12 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
13 ↑ ↓ Bash Shell Scripting
- 13.1 ↑ ↓ edit point - shell variable quoting
- 13.2 ↑ ↓ example shell script - back up several databases
- 13.3 ↑ ↓ show kernel version script
- 13.4 ↑ ↓ Other useful shell tutorial references
14 ↑ ↓ Regex tutorials
15 ↑ ↓ `sed` stream editor
16 ↑ ↓ Other Computer Programming Languages
- 16.1 ↑ ↓ Python Scripting Language
- 16.2 ↑ ↓ Expect Utility by Don Libes
- 16.3 ↑ ↓ edit point - Tool command language Tcl
- 16.4 ↑ ↓ edit point - Tcl pattern matching and anchoring, symbols ^ and $ wrt data not lines
- 16.5 ↑ ↓ Rust programming language
- 16.6 ^ C programming notes
- 16.7 ^ C++ references
17 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
18 ↑ ↓ Aboriginal Linux - project now defunct, new project is 'makeroot'
19 ↑ ↓ Linux From Scratch (Separate Article)
20 ↑ ↓ QEMU Emulator
21 ↑ ↓ Embedded Linux Notes, focus on Rpi Linux Kernel Config
22 ↑ ↓ FreeRTOS Notes (Separate Article)
23 ↑ ↓ Bootloader U-Boot
24 ↑ ↓ LPC11U6x Development Board
25 ↑ ↓ avr-libc
26 ↑ ↓ EWAVR, IAR Workbench, Keil compiler notes
27 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
28 ↑ ↓ Yocto References
29 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
30 ↑ ↓ Mobile App Development On Linux
- 30.1 ↑ ↓ Android programming
31 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
32 ↑ ↓ Toradex embedded ARM computers
- 32.1 ↑ ↓ Build U-boot and Linux kernel from source
- 32.2 ↑ ↓ Arduino Development Kit and Documentation
33 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
34 ↑ ↓ Electronics
- 34.1 ↑ ↓ tools and hardware
- 34.2 ↑ ↓ measurement equipment
- 34.3 ↑ ↓ Modbus protocol
35 ↑ ↓ Mathematica
- 35.1 ^ Books on mathematics
- 35.2 ^ Fast Fourier Transform FFT
36 ↑ ↓ Literature
37 ↑ ↓ Other Things To Explore
- 37.1 ^ DYI laptop by Olimex
- 37.2 ↑ ↓ edit point
- 37.3 ↑ ↓ edit point
- 37.4 ↑ ↓ music and lyrics
- 37.5 ↑ ↓ plant and animal references
38 ^ Technology History and Evolution
39 ^ Astronomy
40 ^ Food and Cooking
41 ^ References
42 ^ End of page

↑ ↓ Countries and politics

https://www.nytimes.com/2018/07/28/world/americas/china-latin-america.html

↑ ↓ Community, Culture, the World

Following sections on Community, Geography, Culture, Musica and the world may become a separate wiki page in the future.

↑ ↓ Geography and Place

https://www.usatoday.com/border-wall/story/flight-over-entire-us-mexico-border-fence/605855001/

Morocco weather climate and agriculture . . .

Southeast Environmental School PTSA

Tsagaglalal 'She Who Watches'

https://lebanonuntravelled.com/iris-sofarana-endemic-lebanese-flower/ Iris sofarana endemic to Lebanon

↑ ↓ People

Cultural and envinrmental:

https://www.hcn.org/issues/51.6/tribal-affairs-in-california-the-karuk-tribe-fights-a-growing-wildfire-threat-and-a-lack-of-funding

https://www.opb.org/radio/programs/bbc-outlook/

Encontrado 2019-12-30 lunes, commentario sobre Mahatma Gandhi:

https://www.kolorkomplex.com/kolorkomplex-culture/2017/1/4/mahatma-gandhi

Tech authors, astronomy, more Linux reference material:

↑ ↓ Human languages

English-Hindi glossary at NN

Devanagari conjunct characters

cool new words encountered . . .

US standard Braille and other symbol and language systems

- 2017-12-15 FRI -

↑ ↓ Science

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

- 2017-10-05 - Ted noting here that would be good to have a technical glossary to make easily accessible all the technical terms which arise in daily work and exploration of technologies . . .

- 2017-10-19 - TO-DO list:

  *  [✓] complete LFS 8.1 exercise
  *  [ ] configure xserver to run stand-along without window manager (seems to be working on 1604 spare LTS host . . .)
  *  [ ] set up two mysql servers on one host
  *  [ ] write "best photo contribution" practices page for ASI
  *  [ ] code "re-use or reference text block" module for MediaWiki  <-- this needs further explanation - TMH 
  *  [ ] in local Neela Nurseries PHP code base, amend hybrid building of nav menus to include highlighting parent page of given viewed page
  *  [ ] in OpenCart 2.x find way to customize top-of-page information and links
  *  [ ] in OpenCart 2.x find way to format product lists as compact lists, like Gmail inbox or Windows 'list view' of files

↑ ↓ GNU Make and GCC Tools

2018-07-18 NOTE: this section to be moved to separate GCC and Make article . . . - TMH

https://gcc.gnu.org/onlinedocs/gcc-8.4.0/cpp/Stringizing.html

https://www.gnu.org/software/make/manual/html_node/Special-Targets.html

Using macros with gcc:

https://gcc.gnu.org/onlinedocs/gcc/Option-Summary.html . . . gcc summary of options
https://gcc.gnu.org/onlinedocs/cpp/Macros.html . . . defining macros with -Dmacro_name=expression
https://gcc.gnu.org/onlinedocs/gcc/Preprocessor-Options.html#Preprocessor-Options . . . -MT and other preprocessor options

Code libraries and shared objects, expressing paths to them:

https://gist.github.com/gubatron/32f82053596c24b6bec6

gcc.gnu.org - 3.15 Specifying subprocesses and switches passed to them

https://gcc.gnu.org/onlinedocs/gcc-4.1.2/gcc/Spec-Files.html#Spec-Files

gcc how to show macros and pre-processor defines:

https://stackoverflow.com/questions/2224334/gcc-dump-preprocessor-defines

↑ ↓ OpenOCD and Eagle set up notes

Eagle fails to start due to symbols not resolve-able . . .

 *  https://forums.autodesk.com/t5/eagle-forum/can-t-run-eagle-on-debian-10-testing/td-p/8312348

Automake or autoconf or autoreconf -i fails for LIBTOOL undefined . . .

 *  https://stackoverflow.com/questions/18978252/error-libtool-library-used-but-libtool-is-undefined

 *  https://stackoverflow.com/questions/43565009/failing-to-enable-stlink-in-openocd

↑ ↓ Mediawiki Issues and Notes

- 2018-01-22 - While editing sidebar of Mediawiki instance at Neela, Ted noticing a difference in Mediawiki's treatment of hyperlinks in the sidebar. Links to external sites don't appear, and links to internal pages require single square brace enclosure to appear with alternate text as a link label . . .

<!--
** [https://buildroot.org/downloads/manual/manual.html Buildroot manual]
<a href="https://buildroot.org/downloads/manual/manual.html">Buildroot manual</a>

- 2018-01-22 MON -
** https://wiki.neelanurseries.com/index.php/Nn_embedded_linux_notes#.E2.86.91_.E2.86.93_Buildroot|Buildroot notes . . . only 'notes' shows as non-link text - TMH
-->

^ File uploads

- 2018-06-29 FRI - Issue adding .txt type files to whitelist of Mediawiki installation uploadable files:

Action failed

Could not open lock file for "mwstore://local-backend/local-public/e/ec/Asi-officers-list-2018.txt".

Return to Main Page.

200px|thumb|left|png type image to test file uploads of allowed image type . . .
media:arrow-up-prelight.png

Following link may have helpful information:

https://www.mediawiki.org/wiki/Topic:Qlib7k3p2zvi7pkq

- 2018-07-25 WED -

https://www.mediawiki.org/wiki/Manual:Configuring_file_uploads . . . be sure to examine $wgFileBlacklist in addition to $wgFileExtensions,

^ Images in wiki pages and image attributes

https://en.wikipedia.org/wiki/Wikipedia:Images_linking_to_articles

^ Mediawiki layout topics like multi column layout

- 2018-11-30 FRI -

https://www.mediawiki.org/wiki/Topic:Ube2zt7nhfk51l3s

^ Other Mediawiki topics

https://www.mediawiki.org/wiki/Help:Moving_a_page

↑ ↓ Web Site Building Blocks - Summer 2017 to 2020 Q1 Work

Must begin a new section on web site security issues. Here are a couple of articles as starting points to sleuth out how the "WARNING - Please read me XMG" ransomeware attack can reach MYSQL databases of on-line hosts:

2019-11-12

Web site building blocks . . . now a separate wiki document, as of 2018-01-08. - TMH

2020-01-27 htpasswd access files

https://www.htaccesstools.com/articles/htpasswd/

↑ ↓ Open Source License Types

https://lukasa.co.uk/2012/05/GPL_vs_MIT_Which_License_To_Use/

↑ ↓ Linux Packages (Separate Article)

Linux software package notes a separate wiki document on Neela wiki. - TMH

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

↑ ↓ Bash Shell Scripting

Bash (Bourne shell) Quick Reference:

Shell Built-in Variables:

   $0    Name of given shell script itself
   $1    Value of first command line parameter (similarly $2, $3, ...)
   $#    In given shell script the number of command line parameters received
   $*    All of the command line parameters
   $-    Options given to the shell
   $?    Return (or holds) the exit status of the last command
   $$    Process id of given script (really the id of the shell running the script)


Shell test constructs:

SYNTAX      NAME OF SHELL TEST                                NOTES

[           built-in test                                     considers its arguments as comparison expressions or file tests

[[...]]     in Bash => 2.02 the extended test command

((...))     arithmetic tests                                  example:  (( 0 && 1 ))  # Logical AND

References:

http://tldp.org/LDP/abs/html/testconstructs.html

http://tldp.org/LDP/abs/html/internal.html#BUILTINREF

http://tldp.org/LDP/abs/html/string-manipulation.html

Shell scripting and use of built-in shell commands is a practical knowledge to employ, when working in Unix-like environments. One common task is to find all the instances of a given file or program. The locate command can perform this kind of search, but it's results don't show whether the file instances differ. To check at the rough level of file size, we can use a one-line shell script technique involving shell piping, to "long list" the results of the locate command, like this . . .

  $ for file in `locate tavrasm | grep 'asm$'`; do ls -l ${file}; done

Hmm strange, the above command calls `grep` with a pattern that ends in the shell end-of-line anchoring character $, and appears to filter for results of `locate` which end in 'asm'. But on 2017-09-12 needed to add a "one or more wildcard" character pattern to limit search results for instances of `locate` results ending in 'qemu':

    $ locate qemu | grep '.*qemu$'

Why the apparent difference in command invocation? Need to test . . . - TMH

Command to break out first ten $PATH environment variable to individual paths each shown on a line of the shell:

    $ for path in `echo $PATH | cut -d':' -f1-10 --output-delimiter=' '`; do echo $path; done

2018-04-23 - Monday, command to obtain summary of directories containing 1GB or more data:

    $ du -h . | grep [0-9]G

↑ ↓ edit point - shell variable quoting

- 2017-10-19 THU -

Running into issues when need to expand shell variable in single quotes pair . . .

Stack Exchange, Unix forum post 178411
TLPD Advanced Bash Scripting Guide, chapter 4.2 example 4-3 double quotes preserve white space

WIKI WISH LIST - While adding to wiki, Ted noting that would be useful to have relative-depth wiki section markers. The standard wiki section markers '== ==', '=== ===' and similar have fixed depth. That is, '== ==' is always a top-level or first-level section in a wiki document, '=== ===' is always a sub-subsection of wiki documents, and '==== ====' a sub-sub-section. When section gets re-factored into its own article, would be handy to have those section markers rise up to levels of top-most and successive section markers. - TMH

↑ ↓ example shell script - back up several databases

Here is a simple shell script to call mysqldump utility and back up several databases. Couple of things Ted wants to add to this script include script variables to hold back-up filename prefix and infix patterns, and an option to compress the MYSQL dump files . . .

Figure x - shell script to back-up multiple MYSQL databases


#!/bin/bash


DATABASE_LIST="information_schema mysql drupal_8p0 phpmyadmin wiki_database"

user="root"
pass_phrase_for_mysql="mysql_user_password"
options_extra="--skip-lock-tables"

response="n"

mode_interactive="n"



echo "shell script starting,"



for database in ${DATABASE_LIST};
do echo "backing up alta-ubuntu database $database . . .";

#    command="mysqldump --databases $database -u$user -p$pass_phrase_for_mysql $options_extra >> au-database-back-up--${database}.sql"
    command="mysqldump --databases $database -u$user -p$pass_phrase_for_mysql $options_extra"
    redirect="au-database-back-up--${database}.sql"

    if [ $mode_interactive = 'y' ]; then

        echo "build command '$command' and database back-up filename'$redirect',"
        echo "full command will be '$command' > '$redirect',"
        echo "trying running this command and redirect? [y/N/q]  yes, no, 'q' to quit"

        read response
        if [ $response = 'Y' -o $response = 'y' ]; then
            ${command} > $redirect
        elif [ $response = 'N' -o $response = 'n' ]; then
            echo "skipping present command . . ."
        elif [ $response = 'Q' -o $response = 'q' ]; then
            echo "stopping script '$0' and exiting."
            break
        fi
        echo

    else

        echo "$0:  backing up database '$database' to file '$redirect' . . ."
        ${command} > $redirect
        ls -l $redirect

    fi

done


echo "done."

exit 0

↑ ↓ show kernel version script

Following script 'showkversion' can be used in a Linux kernel source tree to determine the kernel's version number, based on the number elements defined in the kernel's top level makefile.

Figure x - simple bash script to show kernel version in root of kernel sources tree

#!/bin/bash

## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
## Started 2017-12-15 FRI - script to parse and show Linux kernel
##  version from top-level makefile in set of kernel sources.  Patterns
##  to `grep` chosen based on kernel version identifiers in first
##  three lines of typical kernel top-level makefile.  Example:
##
##  $ head -n 6 Makefile
##  VERSION = 4
##  PATCHLEVEL = 9
##  SUBLEVEL = 66
##  EXTRAVERSION =
##  NAME = Roaring Lionus
##
##
## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -


script_name="showkversion"


if [ ]; then
    head -n 5 Makefile | grep ^VERSION | cut -d " " -f 3
    head -n 5 Makefile | grep ^PATCH | cut -d " " -f 3
    head -n 5 Makefile | grep ^SUBLEVEL | cut -d " " -f 3
fi

MAJOR=$(head -n 5 Makefile | grep ^VERSION | cut -d " " -f 3)
MINOR1=$(head -n 5 Makefile | grep ^PATCH | cut -d " " -f 3)
MINOR2=$(head -n 5 Makefile | grep ^SUBLEVEL | cut -d " " -f 3)

KERNEL_REVISION="${MAJOR}.${MINOR1}.${MINOR2}"

echo
echo "Kernel version in present kernel sources tree, per makefile, is ${KERNEL_REVISION}"
echo


exit 0

↑ ↓ Other useful shell tutorial references

http://tldp.org/LDP/abs/html/textproc.html . . . commands cut, paste, join and others
https://unix.stackexchange.com/questions/131766/why-does-my-shell-script-choke-on-whitespace-or-other-special-characters . . . read shell input line by line
https://stackoverflow.com/questions/7427262/how-to-read-a-file-into-a-variable-in-shell . . . read file into shell variable

↑ ↓ Regex tutorials

https://www.ntu.edu.sg/home/ehchua/programming/howto/Regexe.html

2019-11-02 - An interesting blog post and replies, at, I think, Jamie Zawinski's home page. This one on the use and some limits of regular expressions:

  *  https://www.jwz.org/blog/2011/11/you-doom-us-all-to-inhuman-toil-for-the-one-whose-name-cannot-be-expressed-in-the-basic-multilingual-plane/

↑ ↓ `sed` stream editor

Unix `sed` stream editor, examples and references:

Code snippet - rename multiple files where a substring need be changed:

   $ for file in `ls ./2109*.*`; do mv $file `ls -1 $file | sed s/2109/2019/` ; done

References on `sed`:

http://www.grymoire.com/Unix/Sed.html#uh-1

2021-08-26:

https://unix.stackexchange.com/questions/375530/use-sed-to-find-and-replace-a-string-in-multiple-files

↑ ↓ Other Computer Programming Languages

↑ ↓ Python Scripting Language

https://docs.python.org/2/tutorial/index.html

https://learn.onemonth.com/ruby-vs-python/

↑ ↓ Expect Utility by Don Libes

Installing 'expect' on Ubuntu 16.04.x LTS host, typical dependencies:

ted@localhost:~/projects/shell/expect-work$ sudo apt install expect

Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following additional packages will be installed:
  libfontenc1 libxaw7 libxmu6 libxmuu1 libxtst6 libxv1 libxxf86dga1 tcl-expect tcl8.6 tk8.6 x11-utils xbitmaps xterm
Suggested packages:
  tcl-tclreadline mesa-utils xfonts-cyrillic
The following NEW packages will be installed:
  expect libfontenc1 libxaw7 libxmu6 libxmuu1 libxtst6 libxv1 libxxf86dga1 tcl-expect tcl8.6 tk8.6 x11-utils xbitmaps xterm
0 upgraded, 14 newly installed, 0 to remove and 5 not upgraded.
Need to get 1,373 kB of archives.
After this operation, 4,110 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
  .
  .
  .

Some 'expect' utility references:

https://www.unix.com/shell-programming-and-scripting/176054-multiple-while-loops-expect-script.html?s=3aa3009c43b2e834326eea6dfa0d1139

Good short examples covering range of tasks here at Robert Elder blog page, noting md5sum expect script example . . .

http://blog.robertelder.org/don-libes-expect-unix-automation-tool/

https://www.ibm.com/developerworks/community/blogs/brian/entry/when_to_use_expect_scripting_and_when_to_avoid_it10?lang=en Expect script with while-loop

https://wiki.tcl.tk/11584 list of Expect tutorials

https://debaan.blogspot.com/2007/09/simple-expect-ssh-example.html

http://wiki.tcl.tk/11583

How to capture specific results during an expect script's execution:

https://stackoverflow.com/questions/2077721/how-do-you-save-and-parse-a-command-output-in-expect

- 2018-01-30 - Tuesday, picking up from last week researching how to redirect expect output and its spawned processes' output with filtering to log file. The first reference here at Stackoverflow repeats the useful lindex syntax. There is also mention of the expect manual and a syntax $::env(action) which can be expressed in an expect script to access an environment variable that is part of the controlling shell . . .

https://stackoverflow.com/questions/11131318/how-to-use-bash-script-variables-in-expect-conditional-statements

How to use expect's log_file key word in an expect script:

https://stackoverflow.com/questions/15965504/how-to-create-log-file-for-tcl-script

From the manual page for expect version 5.45:

log_file [args] [[-a] file] If a filename is provided, log_file will record a transcript of the session (beginning at that point) in the file. log_file will stop recording if no argument is given. Any previous log file is closed. Instead of a filename, a Tcl file identifier may be provided by using the -open or -leaveopen flags. This is similar to the spawn command. (See spawn for more info.) The -a flag forces output to be logged that was suppressed by the log_user command. By default, the log_file command appends to old files rather than truncating them, for the convenience of being able to turn logging off and on multiple times in one session. To truncate files, use the -noappend flag. The -info flag causes log_file to return a description of the most recent non-info arguments given.

Also from the expect manual page, Expect Hints section:

EXPECT HINTS There are a couple of things about Expect that may be non-intuitive. This section attempts to address some of these things with a couple of suggestions. A common expect problem is how to recognize shell prompts. Since these are customized differently by differ- ently people and different shells, portably automating rlogin can be difficult without knowing the prompt. A reasonable convention is to have users store a regular expression describing their prompt (in particular, the end of it) in the environment variable EXPECT_PROMPT. Code like the following can be used. If EXPECT_PROMPT doesn't exist, the code still has a good chance of functioning correctly. set prompt "(%|#|\\$) $" ;# default prompt catch {set prompt $env(EXPECT_PROMPT)} expect -re $prompt I encourage you to write expect patterns that include the end of whatever you expect to see. This avoids the possibility of answering a question before seeing the entire thing. In addition . . .

The expect program has some built-in string buffers, and one of these may hold the latest characters received from a spawned process. Here is a man page excerpt which shows use of one of these expect buffers:

disconnect disconnects a forked process from the terminal. It continues running in the background. The process is given its own process group (if possible). Standard I/O is redirected to /dev/null. The following fragment uses disconnect to continue running the script in the background. if {[fork]!=0} exit disconnect . . . The following script reads a password, and then runs a program every hour that demands a password each time it is run. The script supplies the password so that you only have to type it once. (See the stty command which demonstrates how to turn off password echoing.) send_user "password?\ " expect_user -re "(.*)\n" for {} 1 {} { if {[fork]!=0} {sleep 3600;continue} disconnect spawn priv_prog expect Password: send "$expect_out(1,string)\r" . . . exit }

Further looking for expect's built-in string buffers and variables . . .

http://wiki.tcl.tk/17378

Pattern matching syntax in Don Libe's expect . . .

http://www.embecosm.com/appnotes/ean8/html/ch03s02s01.html

https://www.pantz.org/software/expect/expect_examples_and_tips.html . . . some timing stuff and expect script blocks

http://www.asic-world.com/scripting/tcl3.html . . . regex in Tcl must enclose pattern in braces.

From another source, Tcl's string match command:

if [string match "f*b*" "foobar"] {
   puts "match"
else {
   puts "no match"
}

↑ ↓ edit point - Tool command language Tcl

"Practical programming
in Tcl and Tk"
ISBN 0-13-038560-3

In using Don Libes' expect utility or program, looks like it will be important and helpful to understand Tool Command Language Tcl to at least some fluency. Here appears to be a good starting point tutorial for Tcl:

https://www.tutorialspoint.com/tcl-tk/tcl_commands.htm

Tcl puts built-in command, channels and code to open log file,

https://www.tcl.tk/man/tcl8.4/TclCmd/puts.htm

Append a log message to a file:

set chan [open my.log a]
set timestamp [clock format [clock seconds]]
puts $chan "$timestamp - Hello, World!"
close $chan

Tcl regular expressions:

https://www.tcl.tk/man/tcl8.2.3/TclCmd/re_syntax.htm

Tcl reserved words:

after		append		array		auto_execok
auto_import	auto_load	auto_load_index	auto_qualify
binary		Bgerror		break		catch
cd		Clock		close		concat
continue	Dde		default		else
elseif		Encoding	eof		error
eval		Exec		exit		expr
fblocked	Fconfigure	fcopy		file
fileevent	Flush		for		foreach
format		Gets		glob		global
history		If		info		interp
join		Lappend		lindex		linsert
list		Llength		load		lrange
lreplace	Lsearch		lsort		namespace
open		Package		pid		pkg_mkIndex
proc		Puts		pwd		read
regexp		Regsub		rename		resource
return		Scan		seek		set
socket		Source		split		string
subst		Switch		tclLog		tell
time		Trace		unknown		unset
update		Uplevel		upvar		variable
vwait		While

↑ ↓ edit point - Tcl pattern matching and anchoring, symbols ^ and $ wrt data not lines

From the Tcl manual page on-line here is a clue about pattern matching in Tcl scripts, which may explain why we are struggling to obtain matched substrings from sequences of bytes from expect-spawned processes . . .

Note that in many editors, the ^ and $ match the beginning and end of lines respectively. However, because expect is not line oriented, these characters match the beginning and end of the data (as opposed to lines) currently in the expect matching buffer. (Also, see the note below on "system indigestion.")

Tcl regular expression syntax:

https://www.tcl.tk/man/tcl8.2.3/TclCmd/re_syntax.htm#M57

Expect variables, using global and upvar keywords in Tcl scripts:

http://www.huecker.com/msw/tcl/tutorial/Tcl13.shtml

Excerpt on Tcl pattern matching from Inguza web site:

2   Expect
The expect suite actually consist just of a few commands: expect, send, spawn and interact and is an extension to TCL.
Before the expect command can be used a program must be spawned, see expect commands below.
expect \
  {match1} {action1} \
  {match2} {action2} \
  {match3} {action3} \
  {match4} {action4}
It is possible that no such output is encountered within the time period defined by the timeout (variable name "timeout" in seconds, default to 2). In this case expect stops waiting and continues with the next command in the script.
You can use '*' to match any characters. You can also match using [] syntax and similar.
expect "\[a-f0-9]"  ; # strongly preferred as \n and similar is not taken as litteral charactesr \ and n.
expect {a-f0-9}     ; # can also be used
A note on \ characters. The pattern matcher translate \x to x but this is done once before the pattern matcher. So you need to type \\n to match n. This is especially important for * and ? characters.
expect "*" ;# match anything (*)
expect "\n" ;# match linefeed
expect "\*" ;# match anything
expect "\\*" ;# match * character
expect "\\\*" ;# match * character
expect "\\\\*" ;# match \ followed by anything
expect "\\\\\*" ;# match \ followed by anything
expect "\\\\\\*" ;# match \ followed * character
The [ character is special to both tcl and the pattern matcher so it is especially messy.
proc xy {} { return "n*w" }
expect "[xy]" ;# match n followed by anything followed by w
expect "\[xy]" ;# match x or y
expect "\\[xy]" ;# match n followed by anything followed by w
expect "\\\[xy]" ;# match [xy]
expect "\\\\[xy]" ;# match \ followed by n followed ...
expect "\\\\\[xy]" ;# match sequence of \ and then x or y.
The expect command can also take flags. The default flag is -gl for glob pattern matching. It can also take the flag -re for regular expression matching.
expect {
  -re "a*" { action_when_a_followed_by_any_a }
  "b*" { action_when_b_followed_by_anything }
  -gl "-re" { action_when_real_dash_r_e }
  eof { action_on_end_of_file }
  timeout { action_on_command_timeout }
  default { action_on_command_timeout_or_eof }
  -re "(abc)*" { action_on_any_number_of_a_b_c }
  -re "-?(0|\[1-9]\[0-9]*)?\\.?\[0-9]*" { action_on_float_or_integer }
}
You can also pass the pattern as a variable.
set v2pats "pat2 act2"
set v3pats "pat3 act3"
expect pat1 act1 $v2pats $v3pats
Observe that the following expect string is wrong as $v2pats and $v3pats is considered as two different arguments. It will try to match $v2pats as a pattern and $v3pats as an action. Instead build up a string and use the -brace flag. You can not use double quotes for that though, unless you use eval and then the -brace flag is not necessary. You also need to protect the pattern and action inside a [list x] or an extra brace if they contain whitespaces.
2.1   Parentheses for feedback
In the previous section, parantheses were used to group subpatterns together. They can also play another role. When a regular expression successfully matches a string each part of the string that matches a paranthensized subpattern is stored in "expect_out(1,string)" the second in "expect_out(2,string)" etc up to "expect_out(9,string)". The entire pattern matched is stored in "expect_out(0,string)". Everthing before the pattern and the pattern matched is stored in "expect_out(buffer)". The last two assignments work in glob pattern too.
"a*((ab)*|b)"
How is this passed to expect_out? It is quite simple. The entire string withing the first parenthesis is stored in 1 (which means up to end of string). The second fount parenthesis is stored in 2. Look for the left parenthesis to determine where the data is put.
2.2   Flags
-re	
-gl	
-nocase	Ignore case. Do not use -nocase with uppercase characters in the pattern as it will never match.
-notransfer	Prevent expect from removing matching characters from the internal buffer. The characters can be matched repeatedly as long as this option is associated with the pattern. It can be abbreviated with "-n" when expect is running interactively.
-brace	Expect normally see the first argument as a pattern to match, but sometimes you want to give a list of patterns and actions to expect. You can then use -brace to expand the list before it is handled by expect.
expect -brace { pat1 act1 pat2 act2 }
This can be useful when building up lists of pattern to match with corresponding actions to do.
-i n	Use an alternative spawn_id. This applies to all patterns after the -i flag.
expect {
 -i $ftp
 "ftp>" "exit"
 eof "exit"
}
You can also expect values from multiple spawned processes at the same time. At most one action can be executed just as expect normally do.
expect {
 -i $ftp "ftp> " { ftp_action }
 -i $shell $prompt { shell_action }
}
There is an input buffer associated with each spawn id. So any output from ftp is kept separate from thta of the shell in the example above. When output appear on terminal it will be mixed, unless you expect one at a time or set log_user 0 and then wrote output explictly using send_user $expect_out(buffer). The process that did not match will keep its buffer until matched by next expect command.
When the expect command match something it record the spawn_id to expect_out(spawn_id) so you can know which process that it matched against.
You can also set the spawn_id definition to a list of spawn_ids.
expect {
  -i "$host1 $host2 $host3" $prompt {
    an_action $expect_out(spawn_id)
  }
  eof exit
  -i $host1 another_pattern {host1_action}
}
This example will do an_action if $prompt is matched agains any of the $hostnr, exit if end of file is matched against same list and do host1_action if matchina another_pattern from host1.
2.3   Special patterns
Note that these patcherns will only match if none of the '-gl', '-re' or '-ex' flags has been used.
eof	Match when end of file is reached.
timeout	Match when the timeout value has been reached.
default	Match when end of file or timeout is reached.
full_buffer	Match when no other pattern match and expect would otherwise throw away part of the input to make room fore more. When this matches, all of the unmatched input is moved to expect_out(buffer).
null	
By default null characters are removed from the buffer before expect matching is done. This can be disabled using the remove_nulls command below. If it is disabled null characters will be matched using this special keyword. Null characters can not be matched inside a pattern as expect first look for null characters and then do pattern matching. If a null character is found the characters before it is skilled. These caracters can be found in expect_out(buffer).
Since the null character is used internally to represent the end of a string unanchored patterns cannot be matched past a null. This is not a problem since null pattern can always be listed last.

↑ ↓ Rust programming language

There are two editions of the Rust Programming book. The Rust home page recommends to start by reading the second edition:

https://doc.rust-lang.org/book/second-edition/

https://doc.rust-lang.org/nomicon/

^ C programming notes

This section really should be in a more prominent space of this wiki. - TMH

This section contains link to Brian Barto post about Untangling Complex C Declarations. Click here -> C programming notes <- for separate wiki article.

Typedef and type defining function pointers:

2019-06-11 https://www.learncpp.com/cpp-tutorial/78-function-pointers/

CRC types and implementations:

https://stackoverflow.com/questions/10564491/function-to-calculate-a-crc16-checksum

Floating point representation and conversions:

http://www.ryanjuckett.com/programming/printing-floating-point-numbers/

https://medium.com/@bartobri/untangling-complex-c-declarations-9b6a0cf88c96 "I liked this post about untangling complicated pointer declarations and operators - T.D."

2021-11-03

https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.47.1127&rep=rep1&type=pdf

^ C++ references

This section contains beginning level C++ issues and references. Section here created by need to note some Qt5 related project elements, as Qt is based on C++. First issue is to understand and document how to implement a QDialog object to act as a sensible dialog box, which can post run-time data to a larger Qt based application. The first reference below mentions QDialog built-in class functions exec(), accept() and reject(), which appear to be the means to start and show, and to close out a Qt based dialog box . . .

https://stackoverflow.com/questions/12470806/qdialog-exec-and-getting-result-value

Per help index in QtCreator 3.2.1:

void QDialog::accept() [virtual slot] Hides the modal dialog and sets the result code to Accepted. See also reject() and done().

The Qt method done() performs more significant work and at least in cases of a dialog being shown with a call to exec() the done() method stops dialog event loop execution:

void QDialog::done(int r) [virtual slot] Closes the dialog and sets its result code to r. If this dialog is shown with exec(), done() causes the local event loop to finish, and exec() to return r. As with QWidget::close(), done() deletes the dialog if the Qt::WA_DeleteOnClose flag is set. If the dialog is the application's main widget, the application terminates. If the dialog is the last window closed, the QApplication::lastWindowClosed() signal is emitted. See also accept(), reject(), QApplication::activeWindow(), and QApplication::quit().

So it looks like if we do not call done() then we want to assure that we call exec() only one time during a use session of GWN Unified Tester. - TMH

2019-10-28 Monday: G++ error, "template has C linkage":

https://stackoverflow.com/questions/4877705/why-cant-templates-be-within-extern-c-blocks

2019-10-30 Wednesday: The purposes and use of extern "C" . . .

https://stackoverflow.com/questions/1041866/what-is-the-effect-of-extern-c-in-c

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

↑ ↓ Aboriginal Linux - project now defunct, new project is 'makeroot'

Ok, looks like Robert Landley's Aboriginal Linux project has been superceded by mkroot. Ladnley's newer makeroot project sources are available at GitHub:

makeroot project on GitHub

Having trouble carrying out the basic build of Aboriginal Linux with armv6l as target . . .


   .
   .
   .

Confirmed e2fsprogs-1.42.13.tar.gz
Confirmed zlib-1.2.7.tar.bz2
Confirmed squashfs-4.2.tar.gz
=== Got all source.

real    0m2.240s
user    0m1.188s
sys     0m0.176s
=== toybox (host host-tools)
Snapshot 'toybox'...
scripts/genconfig.sh
cc -o kconfig/conf kconfig/conf.c kconfig/zconf.tab.c -DKBUILD_NO_NLS=1 \
                -DPROJECT_NAME=\"ToyBox\"
kconfig/conf -D /dev/null Config.in > /dev/null
scripts/make.sh
Generate headers from toys/*/*.c...
generated/newtoys.h Library probe.......
Make generated/config.h from .config.
generated/flags.h generated/globals.h generated/help.h
Compile toybox................................................................................................................................................................generated/obj/nsenter.o: In function `unshare_main':
nsenter.c:(.text.unshare_main+0x152): undefined reference to `setns'
collect2: error: ld returned 1 exit status
make: *** [toybox] Error 1

Exiting due to errors (host host-tools toybox)

Linux kernel routine to setns()

Robert Landley also has a presence on www.patreon.com/landley, where he talks about the over-arching goals in his programming and software systems level work.

↑ ↓ Linux From Scratch (Separate Article)

Linux From Scratch Book 8.1 - Build and Notes

↑ ↓ QEMU Emulator

Overview

Notes on QEMU, an emulator which can help with building and configuring Linux systems to run on embedded computers and development boards. Ted noting 2017-09-08 that to compile today's latest QEMU source, a 2.10.x release, needed to install Debian stretch packages pkg-config, libglib2.0-dev, dhautoreconf. Here are some links to downloading QEMU project sources, a manual for using QEMU, and an article about emulating a RaspberryPi system by using QEMU:

References:

QEMU to emulate Arm on Linux . . .

How to avoid "raw image format" warning . . .

https://unix.stackexchange.com/questions/276480/booting-a-raw-disk-image-in-qemu

So got QEMU 2.10.0 sources and dependencies installed, ran `configure` and `make` steps, and let the build process run for an hour or two. But in the end could not find any `qemu` executable. Why is the emulator itself apparently missing? Building latest QEMU under Linux . . .

Building QEMU on Linux type hosts

So I'm following the above article author's typical build steps, and run into this message part-way down those steps, at the step of calling `make`:

user@host-6:~/Downloads/qemu/qemu-2.10.0/bin/debug/native$ make
Makefile:21: *** This is an out of tree build but your source tree (/home/veris/Downloads/qemu/qemu-2.10.0) seems to have been used for an in-tree build. You can fix this by running "make distclean && rm -rf *-linux-user *-softmmu" in your source tree.  Stop.
user@host-6:~/Downloads/qemu/qemu-2.10.0/bin/debug/native$

Ok interesting, I know that QEMU is a complicated project with a complex build process, but clearly I don't know what I'm doing. Following the above 'distclean' command given in the error message from QEMU's makefile, I'm now able to begin an "out of tree" build as described in the "Building QEMU" article at qemu.org just above. Tired already however of QEMU project builds taking more than an hour to complete. Here is one of many articles describing how to invoke `make` to build only limited parts of QEMU project, for example just the pieces needed to emulate ARM type systems:

Build qemu-system-arm on Linux host

Ted to test this type of build soon . . .

On a different note, QEMU build has completed and the stock RaspberryPi Debian "Stretch" image is coming up. Needed to install a VNC client to interact with the emulated RaspberryPi operating and software, stored in the downloaded .img file from Rpi's web site. Here's a link to a forum post which clued Ted into Remmina VNC client:

Quora dot com, connect to VNC server

- 2017-11-21 Tuesday -

The version of qemu which installed from Debian's package list didn't seem to work. It's been some weeks now since trying that instance, but qemu 2.10.0 works to bring up a command line image built for RaspberryPi. Here are the versions of the two qemu instances:

Figure x - locating qemu instances, determining their versions


user@localhost:~$ which qemu
/usr/bin/qemu

user@localhost:~$ /usr/bin/qemu --version
QEMU emulator version 1.1.2 (Debian 1.1.2+dfsg-6+deb7u23), Copyright (c) 2003-2008 Fabrice Bellard

user@localhost:~$ ls /opt/qemu
qemu-system-arm

user@localhost:~$ ls -l /opt/qemu/qemu-system-arm
lrwxrwxrwx 1 root root 83 Sep 12 16:37 /opt/qemu/qemu-system-arm -> /home/user/Downloads/qemu/qemu-2.10.0/bin/debug/native/arm-softmmu/qemu-system-arm

user@localhost:~$ /opt/qemu/qemu-system-arm --version
QEMU emulator version 2.10.0
Copyright (c) 2003-2017 Fabrice Bellard and the QEMU Project developers

user@localhost:~

- 2017-11-22 Wednesday -

Yesterday could not bring up raspbian image in qemu, same image which booted and appeared, and permitted shell based login and shell use a month ago on the local host. Looking at a new on-line reference for running raspbian images in qemu:

  *  https://ownyourbits.com/2017/02/06/raspbian-on-qemu-with-network-access/

This above article looks really interesting, appears to go to a second installment of the article where the developers there are building some kind of cloud-based or cloud involved web, database, mail and PHP servers. But on my end having trouble with a kernel panic this morning when invoking qemu-system-arm with a large set of options . . . ok, just located a different invocation of qemu-system-arm version 2.10.0, noting here in following code figure:

Figure x - emulate-rpi shell script


#!/bin/bash
# Starts raspberry pi image in configuration mode


##----------------------------------------------------------------------
## - SECTION - script variables
##----------------------------------------------------------------------

EMULATOR=/home/veris/Downloads/qemu/qemu-2.10.0/bin/debug/native/arm-softmmu/qemu-system-arm



##----------------------------------------------------------------------
## - SECTION - original emulator invocation, everything hard-coded
##----------------------------------------------------------------------

# qemu-system-arm -kernel ./qemu-rpi-kernel/kernel-qemu -cpu arm1176 -m 256 -M versatilepb -no-reboot -serial stdio -append "root=/dev/sda2 panic=1 rootfstype=ext4 rw init=/bin/bash" -hda rpi.img

# qemu-system-arm -kernel ./qemu-rpi-kernel/kernel-qemu -cpu arm1176 -m 256 -M versatilepb -no-reboot -serial stdio -append "root=/dev/sda2 panic=1 rootfstype=ext4 rw" -hda rpi.img



##----------------------------------------------------------------------
## - SECTION - invocation, emulator as variable:
##----------------------------------------------------------------------

# ${EMULATOR} -kernel ./qemu-rpi-kernel/kernel-qemu -cpu arm1176 -m 256 -M versatilepb -no-reboot -serial stdio -append "root=/dev/sda2 panic=1 rootfstype=ext4 rw init=/bin/bash" -hda rpi.img

# Start RaspberryPi in fully functional mode:
${EMULATOR} -kernel ./qemu-rpi-kernel/kernel-qemu -cpu arm1176 -m 256 -M versatilepb -no-reboot -serial stdio -append "root=/dev/sda2 panic=1 rootfstype=ext4 rw" -hda rpi.img






## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
## 2017-09-08 FRI - this script copied from http://embedonix.com/articles/linux/emulating-raspberry-pi-on-linux/
## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

exit 0

The final token rpi.img points to localhost:/home/user/Downloads/raspberrypi/2017-08-16-raspbian-stretch-lite.img which we downloaded from https://www.raspberrypi.org/downloads/raspbian/. The working qemu invocation doesn't open qemu's native window, but puts to standard out that is the same shell in which qemu invoked, a couple of lines of output from the booting kernel image. Then using remmina we connect via "VNC server running on ::1:5900".

In summary shell script in latest figure successfully invokes qemu-system-arm 2.10.0 built from sources about August 2017, and boots up Raspbian Stretch lite image and kernel named kernel-qemu-4.4.34-jessie. Next figure is screenshot showing successful login, and last login message . . . though emulation was and is very slow on host system!

Figure x - emulated raspbian stretch lite screenshot, Remmina window

media:z.png

A shorter script to start raspberrypi kernel plus image, running in QEMU:

#!/bin/bash

qemu-system-arm -kernel ./kernel-qemu-4.4.34-jessie -cpu arm1176 -m 256 -M versatilepb -serial stdio -append "root=/dev/sda2 rootfstype=ext4 rw" -hda ./2017-09-07-raspbian-stretch-lite.img -redir tcp:5022::22 -no-reboot

exit 0

- 2017-12-12 WED -

An excerpt from qemu.org/download#source, on how to download, configure and compile latest QEMU sources:

"
Build instructions

To download and build QEMU 2.11.0-rc5:

wget https://download.qemu.org/qemu-2.11.0-rc5.tar.xz
tar xvJf qemu-2.11.0-rc5.tar.xz
cd qemu-2.11.0-rc5
./configure
make

To download and build QEMU from git:

git clone git://git.qemu.org/qemu.git
cd qemu
git submodule init
git submodule update --recursive
./configure
make

The latest development happens on the master branch. The stable trees are located in branches named stable-X.YY branch, where X.YY is the release version.
"

↑ ↓ Embedded Linux Notes, focus on Rpi Linux Kernel Config

2018-11-09 - Ted to create embedded work article on this wiki installation, so noting this Friday evening. - TMH

Ted looking into a couple of areas of embedded Linux, including custom kernel config for Rpi, the open source Buildroot project, Tiny-Core Linux and FreeRTOS. Ted also stashing some links to embedded studies notes on this wiki here:

Copying Rpi Linux partitions to hard disk

↑ ↓ FreeRTOS Notes (Separate Article)

FreeRTOS notes

Ted to move this link to nn wiki article named 'FreeRTOS'. For now however Ted noting an openssl library named Wolfssl:

NOTE 2017-12-10: this section 'embedded operating systems' to become a shorter list of major significant embedded OS's. As of 2017 winter Ted studying couple distributions of embedded Linux and FreeRTOS.

↑ ↓ Bootloader U-Boot

Ted noting after several custom Linux-for-Rpi kernel build attempts that Raspberry Pi board uses a bootloader typically other than GRUB, commonly uses U-boot. A first tutorial . . . also running into U-boot sources makefile calling a project script which fails to find gcc-6, though /usr/bin/gcc is a symlink to that newer gcc . . .

After installing manually some twenty or thirty gcc-6-arm-linux and gcc-6, gcc-7 files, and installing more modern version of build-essentials package from Ubuntu release codenamed 'bionic', can now build u-boot. Tail of messages from build process . . .

  CC      lib/strto.o
  CC      lib/strmhz.o
  LD      lib/built-in.o
  CC      examples/standalone/stubs.o
  CC       CC      lib/strto.o
  CC      lib/strmhz.o
  LD      lib/built-in.o
  CC      examples/standalone/stubs.o
  CC      examples/standalone/hello_world.o
  LD      examples/standalone/libstubs.o
  LD      examples/standalone/hello_world
  OBJCOPY examples/standalone/hello_world.srec
  OBJCOPY examples/standalone/hello_world.bin
  LD      u-boot
  OBJCOPY u-boot.srec
  OBJCOPY u-boot-nodtb.bin
  SYM     u-boot.sym
  COPY    u-boot.bin
  CFGCHK  u-boot.cfg
ted@rangari:/var/local/ted/projects/u-boot$ examples/standalone/hello_world.o
  LD      examples/standalone/libstubs.o
  LD      examples/standalone/hello_world
  OBJCOPY examples/standalone/hello_world.srec
  OBJCOPY examples/standalone/hello_world.bin
  LD      u-boot
  OBJCOPY u-boot.srec
  OBJCOPY u-boot-nodtb.bin
  SYM     u-boot.sym
  COPY    u-boot.bin
  CFGCHK  u-boot.cfg
ted@rangari:/var/local/ted/projects/u-boot$

↑ ↓ LPC11U6x Development Board

↑ ↓ avr-libc

./avr-libc-1.8.0/include/avr/iom8.h:634:#if !defined(__AVR_LIBC_DEPRECATED_ENABLE__)
./avr-libc-1.8.0/include/avr/iom8.h:657:#endif  /* !defined(__AVR_LIBC_DEPRECATED_ENABLE__) */

 .
 .
 .

633 /* Deprecated items */
634 #if !defined(__AVR_LIBC_DEPRECATED_ENABLE__)
635 
636 #pragma GCC system_header
637 
638 #pragma GCC poison SIG_INTERRUPT0
639 #pragma GCC poison SIG_INTERRUPT1
640 #pragma GCC poison SIG_OUTPUT_COMPARE2
641 #pragma GCC poison SIG_OVERFLOW2
642 #pragma GCC poison SIG_INPUT_CAPTURE1
643 #pragma GCC poison SIG_OUTPUT_COMPARE1A
644 #pragma GCC poison SIG_OUTPUT_COMPARE1B
645 #pragma GCC poison SIG_OVERFLOW1
646 #pragma GCC poison SIG_OVERFLOW0
647 #pragma GCC poison SIG_SPI
648 #pragma GCC poison SIG_UART_RECV
649 #pragma GCC poison SIG_UART_DATA
650 #pragma GCC poison SIG_UART_TRANS
651 #pragma GCC poison SIG_ADC
652 #pragma GCC poison SIG_EEPROM_READY
653 #pragma GCC poison SIG_COMPARATOR
654 #pragma GCC poison SIG_2WIRE_SERIAL
655 #pragma GCC poison SIG_SPM_READY
656 
657 #endif  /* !defined(__AVR_LIBC_DEPRECATED_ENABLE__) */

↑ ↓ EWAVR, IAR Workbench, Keil compiler notes

2019-01-03 THU

http://www.keil.com/support/man/docs/c51/c51_le_sfr.htm

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↑ ↓ Yocto References

Yocto meta-product project by Toradex

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

↑ ↓ Mobile App Development On Linux

https://www.raywenderlich.com/122189/introduction-to-open-source-swift-on-linux
http://www.instructables.com/id/Creating-your-first-iOS-app/
https://developer.apple.com/support/purchase-activation/ . . . required fees to Apple company

- 2018-10-12 FRI -

https://developer.apple.com/documentation/corebluetooth

- 2018-01-15 MON -

https://andrewmichaelsmith.com/2017/02/developing-an-ios-app-on-linux-in-2017/ . . . Developing an iOS app on Linux in 2017
https://itsfoss.com/mount-iphone-ipad-ios-7-ubuntu-13-10/ . . . Ubuntu mount iPhone via libimobiledevice4 libimobiledevice-dev libimobiledevice-util and others
https://beebom.com/how-use-iphone-with-linux/

↑ ↓ Android programming

https://www.ntu.edu.sg/home/ehchua/programming/android/Android_3D.html

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

↑ ↓ Toradex embedded ARM computers

Search for Toradex asymmetric core 'system on a module' board:

104446-colibri-arm-som-imx6ull-datasheet.pdf . . . looks like this may be only single core, not dual heterogeneous core

It looks like Colibri iMX7S and iMX7D are two-core and three-core processor based modules, with asymmetric cores to handle different kinds of data processing more efficiently,

Toradex PN: 00391100 - Colibri iMX7 Dual 1GB | V1.1A
Toradex PN: 01351101 - Iris carrier board

Looks like the Iris carrier board is a smaller form, less featured but more economical carrier board to support use of iMX7D/S systems on modules:

https://developer.toradex.com/products/iris-carrier-board

Software to install on this module:

https://www.toradex.com/computer-on-modules/colibri-arm-family/nxp-freescale-imx7

Software projects and stacks to run on asymmetric core systems:

https://community.nxp.com/docs/DOC-104422

↑ ↓ Build U-boot and Linux kernel from source

https://developer.toradex.com/knowledge-base/build-u-boot-and-linux-kernel-from-source-code

↑ ↓ Arduino Development Kit and Documentation

Looking into Arduino boards as a means to configure an I2C protocol programmer . . .

Arduino Uno development board datasheet:

https://www.farnell.com/datasheets/1682209.pdf

Arduino IDE software download:

https://www.arduino.cc/en/Main/Software

Getting started:

https://www.arduino.cc/en/Guide/HomePage
- https://www.arduino.cc/en/Guide/Linux

A more specifically purposed interface and or programming board called 'Aardvark' . . .

https://www.totalphase.com/support/articles/200468316

FreeRTOS on Arduino development boards . . .

https://github.com/feilipu/Arduino_FreeRTOS_Library

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

↑ ↓ Electronics

https://www.sparkfun.com/products/18572

Transistor, FETs, Op-amps . . .

https://www.electronics-tutorials.ws/amplifier/transistor-biasing.html
http://bg-electronics.de/shop/product_info.php/products_id/6409/language/en . . . MPSA14 Darlington pair NPN transistor

Photovoltaics . . .

https://www.digikey.com/en/articles/techzone/2018/sep/overcoming-power-system-design-challenges-in-1500-vdc-photovoltaic-systems?utm_medium=email&utm_source=tnl&utm_campaign=40284_TNL1811A&utm_content=article1learnmore_US&utm_cid=9726770&mkt_tok=eyJpIjoiWkRFeE1qQmxOMlF4T1dFeCIsInQiOiJLbDVRQkhIUmpGMThyK054VWhLZGFxWmJ5OUpyMHMrdGVKZVdxWnluM1wvRVgxdWcyTzNWQnJrd0wzTlk1SXpqZHZvMWxDNGd4blB3bGFWdWFOSWVsMTNmbWswU1M5aVZhck8wTm1ZK3FBZzFUQXJkK2NZdXlzZng1S2lqTGpob1UifQ%3D%3D

Analog computers

http://www.analogmuseum.org/library/handbook_of_analog_computation.pdf

↑ ↓ tools and hardware

https://www.amazon.com/Illuminated-Jewelers-Trichome-Formline-Supply/dp/B073HWZGP3/ref=sr_1_40?hvadid=241934704451&hvdev=c&hvlocphy=9033803&hvnetw=g&hvpos=1t1&hvqmt=e&hvrand=14352835026335723525

https://docplayer.ru/amp/27429677-32-razryadnyy-kontroller-dlya-aviacionnogo-primeneniya-1986ve1t-k1986ve1t-mdr32f1qi-k1986ve1n4.html

↑ ↓ measurement equipment

2020-10-27

https://saving.em.keysight.com/en/used/oscilloscopes-digital-waveform-analyzers

Not used but I have this 4 channel 100mhz scope that i like a lot. $500 with built-in i2c/spi/uart/canbus decoding https://siglentna.com/product/sds1104x-e-100-mhz/ https://www.youtube.com/watch?v=Kay4Jk2DHuE https://www.youtube.com/watch?v=Cwbwq-AKbPc SiglentSiglent SDS1104X-E (100 MHz) | Siglent Bandwidth: 100 MHz Channels: 4 Real time sampling rate: 1 GSa/s (Total of 2 A-to-D converters) Maximum capture rate: (100,000 in Normal mode, 400,000 in Sequence mode) Memory depth: 14 Mpts Bode Plot function (Requires SIGLENT SDG X or SAG1021 function generator) Search / Navigate functions Web-Based browser remote control Optional Wi-Fi dongle Optional MSO capability YouTubeYouTube | EEVblog EEVblog #1042 - Siglent's $499 SDS1104X-E 4CH Oscilloscope Teardown

↑ ↓ Modbus protocol

Modbus protocol notes

↑ ↓ Mathematica

Mathematical symbols:

Important mathematical topics:

https://en.wikipedia.org/wiki/Pure_mathematics
( applied mathematics link to go here )

^ Books on mathematics

Books on mathematics to explore:

"Lectures and Problems: A Gift to Young Mathematicians (MSRI Mathematical Circles Library)

https://tutorial.math.lamar.edu/classes/calci/IndefiniteIntegrals.aspx Paul's On-line Notes

An excellent book on the FFT is: E. Oran Brigham, The Fast Fourier Transform, PrenticeHall, Englewood Cliffs, NJ, 1974.

CRC, RSA and other mathematical areas . . .

Applied math . . .

https://owlcation.com/stem/Everything-About-Triangles-and-More-Isosceles-Equilateral-Scalene-Pythagoras-Sine-and-Cosine

Fractal geometry and math . . .

Quantum computing and Shor's algorithm . . .

https://en.wikipedia.org/wiki/Shor%27s_algorithm algoritmo de Shor
https://en.wikipedia.org/wiki/Lenstra_elliptic-curve_factorization#Quantum_version_(GEECM) GEECM

---

https://www.cnet.com/pictures/take-a-look-at-googles-quantum-computing-technology/17/

^ Fast Fourier Transform FFT

https://en.wikipedia.org/wiki/Fast_Fourier_transform

https://en.wikipedia.org/wiki/Hexagonal_fast_Fourier_transform

https://mathworld.wolfram.com/FastFourierTransform.html Wolfram Math World, Fast Fourier Transform

↑ ↓ Literature

Liturature and Authors of the World . . .

https://www.literarytraveler.com/articles/tolkien_lewis_england/

↑ ↓ Other Things To Explore

Human health:

https://getpocket.com/explore/item/a-mental-disease-by-any-other-name-2094105417

Here are some technical and science topics to explore, perhaps on a rainy day . . .

Machine learning:

https://github.com/josephmisiti/awesome-machine-learning

Containers and DevOps:

3D Graphics, mathematics behind and programming:

Quaternions and Spatial Rotation

Creative Commons and other Open Source licensed materials:

Dublin Core:

Zdyes mnogo informatsia:

https://ertelecom.ru/t/ru/

^ DYI laptop by Olimex

https://www.olimex.com/Products/DIY-Laptop/

↑ ↓ edit point

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Javascript and JSON:

W3C Schools JSON intro

PC Video, Bochs VBE Extensions:

Perl programming related:

https://perldoc.perl.org/perlpod.html . . . reference to =cut Perl mark-up or directive, plus lots more

Unix and Linux tools, software and building blocks:

nss, Name Service Switch
"Burrows-Wheeler block sorting text compression algorithm", noted 2017-09-29 FRI from LFS 8.1 chapter 6.21 - TMH
https://www.collabora.com/news-and-blog/blog/2017/03/13/kernel-debugging-with-qemu-overview-tools-available/ . . . kernel debugging and kmemleak

https://manned.org/obex-data-server/1d713e98 . . . obex data server

GNU Make book on-line . . .

http://mitechie.com/

Webvanta:

Webvanta cloud-based Content Management System

Virtual server image creation:

Github Users Sharing Their Work:

Michele Mattioni mattions

↑ ↓ edit point

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Cryptography Scientists and Articles:

ARM microcontroller related:

Nested Vector Interrupt Controller (NVIC)

Operating system level programming:

Gputils PIC programming tools, W3C Jigsaw validator referenced at end of page

https://gputils.sourceforge.io/#News

↑ ↓ music and lyrics

https://www.youtube.com/watch?v=Nmqitm6cfuU . . . I am Omni - Back At It - featuring Myka 9

http://ohhla.com/anonymous/blackstr/rm_bside/little_b.blk.txt

https://www.youtube.com/watch?v=RTREDvH8H4g

---

https://www.youtube.com/watch?v=4SpWuseQGys Jew harp, Ted talk and Vilnius

https://www.wish.com/product/59b6c3c68f545e607c2adf30?hide_login_modal=true&from_ad=goog_shopping&_display_country_code=US&_force_currency_code=USD&pid=googleadwords_int&c=%7BcampaignId%7D&ad_cid=59b6c3c68f545e607c2adf30&ad_cc=US&ad_curr=USD&ad_price=48.00&campaign_id=7203534630&gclid=EAIaIQobChMIoZKHvqS06AIVEh-tBh2I6wv-EAQYASABEgKuAvD_BwE&share=web

↑ ↓ plant and animal references

Searching Google and Amazon for bottom heat sources for seed germination:

" Seedfactor MET certified Seedling Heat Mat, Seedfactor Waterproof Durable Germination Station Heat Mat, Warm Hydroponic Heating Pad for Indoor Home Gardening Seed Starter(10" x 20") "

Heating mats article by Jill M. Nicolaus

https://en.wikipedia.org/wiki/Osmia_bicolor
https://nativebeeology.com/mind-your-bees-and-gardens-2/carpenter-bee/ bufflehead mason bee

Aloe references . . .

FOBP284 Rodriguez aloe studies paper

2019-04-10 Cork trees . . .

http://www.corkforest.org/harvesting-the-cork-oak/

Invasive plants . . .

https://www.nybg.org/blogs/plant-talk/tag/amur-cork-tree/

"Planting Instructions 1. Cacti, agaves, and tap-rooted succulents (Aloinopsis, Titanopsis, Nananthus) should be transplanted bare-root. Let the soil in the pot dry out for a few days. Then remove the pot and gently loosen the soil so it falls away from the roots. Trim off any broken roots. Bare root plants should then be planted into a shallow hole. Spread out the roots evenly and sprinkle the soil into the hole until full. The base of the plant should rest on top of the soil. Mulch with a 1⁄2”-1” thick layer of pea-sized gravel around the base of the plant to protect it from contact with soggy soil over the winter months. (See planting diagram on page 12 of our Planting Guide.)

TERMINOLOGY: https://en.wikipedia.org/wiki/Cleistogamy

- 2018-08-06 Monday -

https://www.journals.uchicago.edu/doi/pdfplus/10.1086/277683 . . . lithurge, cactus bees

Wildflowers . . .

http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=p840 . . . lychnis coronaria, rose campion native to Europe
https://en.wikipedia.org/wiki/Silene_coronaria

Iris and Bulbs . . .

http://www.srgc.net/forum/index.php?topic=9952.210 . . . Scottish Rock Garden Club, Pat Toolen seedling PT0343

https://butterfly-conservation.org/moths/identify-a-moth

Personal project notes . . .

bookmarked paths of various projects

2020-10-21

https://www.indefenseofplants.com/blog/2015/7/23/an-orchid-invader-with-an-interesting-ecology helleborine orchid

^ plant pathology

https://www.apsnet.org/publications/phytopathology/backissues/Documents/1971Articles/Phyto61n08_926.PDF

^ Technology History and Evolution

Moore's Law and CMOS scaling ways:

^ Astronomy

Physics topics relating to astronomy:

Black holes and some of their key features as we know them so far:

https://en.wikipedia.org/wiki/Event_Horizon_Telescope
https://en.wikipedia.org/wiki/Kerr_metric Kerr metric as applies to black holes

https://www.shelyak.com/how-to-measure-the-redshift-of-a-galaxy/?lang=en

Black holes and General Relativity . . .

https://en.wikipedia.org/wiki/Chandrasekhar_limit Chandrasekhar Limit of mass of stars and specifically white dwarf stars

^ Food and Cooking

https://getpocket.com/explore/item/the-best-ever-eggplant-parmigiana?utm_source=pocket-newtab Italian eggplant parmigiana

Turkish traditional dishes, borek . . .

https://www.seriouseats.com/2012/02/how-to-make-turkish-burek.html

Search also for simit, imam bayidi, kafta kabab

^ References

Neela Nurseries wiki notes

Reproducible builds, byte-wise reproducible software:

Server Side services . . .

https://www.sslshopper.com/apache-redirect-http-to-https.html

SSL certificates behind firewall

Digital Ocean - How to install MYSQL tutorial

Coding standards:

https://www.kernel.org/doc/html/latest/process/coding-style.html

C and C++:

https://www.tutorialspoint.com/cplusplus/cpp_variable_types.htm "A variable can be declared multiple times but defined only once in a file, routine or code block."

Couple of MediaWiki and publishing issues to look into, which came up during wiki configuration:

Some Hindi language and UTF-8 encoding references, to be factored to a dedicated wiki page later:

Linux programs and utilities:

Graphics Servers:

https://www.reddit.com/r/linux/comments/4bq9kl/eli5_wayland_vs_mir_vs_x11/ X11 versus Wayland compositor

Computer hardware and firmware:

Extensible Firmware Interface, EFI and UEFI, see also LFS Book 8.1 chapter 6.55.2

QEMU

I2C

https://www.nxp.com/docs/en/user-guide/UM10204.pdf

Access iPhone via Linux

https://www.maketecheasier.com/easily-mount-your-iphone-as-an-external-drive-in-ubuntu/

^ End of page

- - - top of page - - -

@@ Line 1: / Line 1: @@
 <center>
--- 2017-07-21 &#x0936;&#x0941;&#x0915;&#x094d;&#x0930;&#x0935;&#x093e;&#x0930; --<br />
+-- 2017-07-21 [[Days_of_the_week|&#x0936;&#x0941;&#x0915;&#x094d;&#x0930;&#x0935;&#x093e;&#x0930;]] --<br />
 User Ted's wiki page at [https://neelanurseries.com Neela Nurseries]<br />
+[[musica|musica, संगीत]]
 </center>
@@ Line 8: / Line 9: @@
 == OVERVIEW ==
-<p>This wiki document a starting point of Ted's notes on Linux use and configuration, Open Source Software and web development.  Recent summer 2017 efforts of Ted's are focused on several high-level programming language and web development frameworks, which can be studied and used separately but are often glued together to achieve meaningful tasks and end-user tools and interfaces.  This personal page of Ted's notes on Neela Nurseries wiki not yet well organized, but here as a quick stash point for holding useful references, and a starting point for more complete and formal documentation.</p>
+<p>This wiki document a starting point of Ted's notes on Linux use and configuration, Open Source Software and web development.
+</p>
+<p>This local notes page on Neela Nurseries wiki not yet well organized, but here as a quick stash point for holding useful references and a starting point for more complete and formal documentation.</p>
+[[Musica|Music notes here]] &nbsp;:::&nbsp; [[Microcontrollers#nn_keywords_template|NN keywords template]] &nbsp;:::&nbsp; [[RTOS#anchor_devzone_forum_posts|Nordic Devzone posts]] &nbsp;:::&nbsp; [https://community.jaredwolff.com/ CircuitDojo Forum] &nbsp;:::&nbsp; [[#to_untangle_c_declarations|Untangling complex C declarations]]
+{|
+|-
+|Keywords:  <code>Untangling</code> <code>Detangling</code> <code>[[#untangling_complex_c_delcarations|Untangling C Declarations]]</code> <code>[[Devzone_posts|Nordic Devzone]]</code> <code>[[Firmware_goals|firmware goals]]</code>
+|}
-__TOC__
+<!-- comment -->
+<span id="quick_links_user_ted"></span><span id="nn_anchor_technical_links"></span>
+== [[#top|^]] Technology and Tools ==
-- 2017-10-05 - Ted noting here that would be good to have a [[technical_glossary|technical glossary]] to make easily accessible all the technical terms which arise in daily work and exploration of technologies . . .
+Quick links to local notes and references: <!--, also available but not consistently synchronized with [[quick_links|stand alone page]] on this wiki: -->
+{| class="wikitable"
-- 2017-10-19 - TO-DO list:
+|- <!-- TABLE ROW : topic group ids -->
+! scope="col" style="min-width: 250px; width: 20%;" | 1
+! scope="col" style="min-width: 250px; width: 20%;" | 2
+! scope="col" style="min-width: 250px; width: 20%;" | 3
+! scope="col" style="min-width: 250px; width: 20%;" | 4
-   *  [&#10003;] complete LFS 8.1 exercise
+|- <!-- TABLE ROW : topic group names -->
-   *  [ ] configure xserver to run stand-along without window manager (seems to be working on 1604 spare LTS host . . .)
+! scope="col" style="min-width: 250px; width: 20%;" | Technical groups
-   *  [ ] set up two mysql servers on one host
+! scope="col" style="min-width: 250px; width: 20%;" | Hardware references
-   *  [ ] write "best photo contribution" practices page for ASI
+! scope="col" style="min-width: 250px; width: 20%;" | Operating systems
-   *  [ ] code "re-use or reference text block" module for MediaWiki <i> &lt;-- this needs further explanation - TMH </i>
+! scope="col" style="min-width: 250px; width: 20%;" | Tools and Toolchains
-   *  [ ] in local Neela Nurseries PHP code base, amend hybrid building of nav menus to include highlighting parent page of given viewed page
-   *  [ ] in OpenCart 2.x find way to customize top-of-page information and links
-   *  [ ] in OpenCart 2.x find way to format product lists as compact lists, like Gmail inbox or Windows 'list view' of files
+<!-- Note on CSS, 'style' tag supports 'width' property:  style="width: 250px;" -->
+|- <!-- TABLE ROW : topic groups -->
+| style="vertical-align: top;" |
+<ul><!-- TOPIC GROUP NAME "Technical groups" -->
-<!-- comment -->
+<li> [https://tldp.org/ The Linux Documentation Project]
+<li> [https://www.kernel.org/ Linux kernel dot org]
+<li> [https://hackaday.io/ Hackaday]
+<li> [https://circuitcellar.com/ Circuit Cellar]
+<li> [https://devzone.nordicsemi.com|Nordic Devzone]
+<li> [[Oresat-notes|Oresat notes]]
-<!-- SECTION - Mediawiki Issues and Notes -->
+<li> <i>Embedded Muse . . . need URL</i>
+<li> [https://www.synopsys.com/designware-ip/technical-bulletin/true-random-number-generator-security-2019q3.html true RNG]
+<li> [[nordic_devzone_posts|Devzone posts and others]]
-== [[#top|&uarr;]] [[#references|&darr;]] Mediawiki Issues and Notes ==
+</ul>
-- 2018-01-22 -
+| style="vertical-align: top;" |
-While editing sidebar of Mediawiki instance at Neela, Ted noticing a difference in Mediawiki's treatment of hyperlinks in the sidebar.  Links to external sites don't appear, and links to internal pages require single square brace enclosure to appear with alternate text as a link label . . .
-<pre>
+<ul><!-- TOPIC GROUP NAME "Hardware references" -->
-<!--
-** [https://buildroot.org/downloads/manual/manual.html Buildroot manual]
-<a href="https://buildroot.org/downloads/manual/manual.html">Buildroot manual</a>
-- 2018-01-22 MON -
+<li>  [[radio|radio]]
-** https://wiki.neelanurseries.com/index.php/Nn_embedded_linux_notes#.E2.86.91_.E2.86.93_Buildroot|Buildroot notes . . . only 'notes' shows as non-link text - TMH
+<li>  [[basic_components|basic components]]
--->
+<li>  [[integrated_circuits|integrated circuits]]
-</pre>
+<li>  [[amplifiers|amplifiers]]
+<li>  [[cell modules|modules_celulares]]
+<li>  [[Microcontrollers|Microcontrollers]]
+<li>  [[dev_boards|dev boards]]
+<li>  [[Arduino notes|arduino-notes]]
+<li>  [[Raspberry_pi|Raspberry Pi notes]]
+<li>  [[memory_devices|memory devices]]
+<li>  [[LoRa|LoRa technology]]
+<li>  [[firmware_programmers|firmware programmers]]
+<li>  [https://www.baldengineer.com/low-side-vs-high-side-transistor-switch.html Baldengineer dot com]
+<li>  [[debuggers|JLink debugger notes]]
+<li>  [[multi-core|multi-core RTOS notes]]
+</ul>
+| style="vertical-align: top;" |
-<!-- comment -->
+<ul><!-- TOPIC GROUP NAME "Operating systems" -->
-<!-- SECTION - Web Site Building Blocks -->
+<li>  [[Zephyr|Zephyr]]
+<li>  [[Containers_and_virtual_machines|Containers and VMs]]
+<li>  [[RTOS|RTOS notes]]
+<li>  [[ThreadX_notes|ThreadX notes]]
+<!-- local pages to review:
+<li>  [[Zephyr_toolchain|Zephyr toolchain]]
+<li>  [[RTOS#.5E_Zephyr_RTOS|Zephyr, west (RTOS page section)]]
+<li>  [[RTOS_Zephyr|Zephyr RTOS (new page 8-18)]]
+-->
+<li>  [[RTOS_topics_general|general RTOS topics]]
+</ul>
-== [[#top|&uarr;]] [[#references|&darr;]] Web Site Building Blocks - Summer 2017 Work ==
+| style="vertical-align: top;" |
-[[nn_web_site_building_blocks|Web site building blocks]] now a separate wiki document, as of 2018-01-08.  - TMH
+<ul><!-- TOPIC GROUP NAME "Tools and toolchains" -->
+<li> [[Make_and_GCC|arm-none-eabi-gcc, gcc, make]]
+<li> [[gdb|gdb]] <font size=1>and general debugging</font>
+<li> [[ld|ld linker]]
+<li> [[clang|clang]]
+<li> [[Openocd-setup|openocd]]
+<li> [[pyocd|pyocd]]
+<li> [[cmake|cmake notes]]
+<li> [[west_zephyr_project_manager|west meta-tool]] <!-- [https://docs.zephyrproject.org/latest/guides/west/index.html west meta-tool] -->
+<li> [[west_manifest_files|west manifest files]]
+<li> [[segger_nordic_version|Segger Nordic version]]
+<li> [[ctags|ctags]] <!-- [[Bazel build tool|bazel_notes]] -->
+<li> [[version_control|version control]]
+</ul>
+|} <!-- CLOSE OF WIKI TABLE -->
+<!--
+==== <i>edit point</i> ====
+-->
+{| class="wikitable"
-<!-- comment -->
+|- <!-- TABLE ROW : topic group ids -->
+! scope="col" style="min-width: 250px; width: 20%;" | 5
+! scope="col" style="min-width: 250px; width: 20%;" | 6
+! scope="col" style="min-width: 250px; width: 20%;" | 7
+! scope="col" style="min-width: 250px; width: 20%;" | 8
-<!-- SECTION - Linux packages -->
+|- <!-- TABLE ROW : topic group names -->
+! scope="col" style="min-width: 250px; width: 20%;" | Documentation
+! scope="col" style="min-width: 250px; width: 20%;" | Programming languages
+! scope="col" style="min-width: 250px; width: 20%;" | Programming languages
+! scope="col" style="min-width: 250px; width: 20%;" | Data Integrity
-== [[#top|&uarr;]] [[#references|&darr;]] Linux Packages (Separate Article) ==
+|- <!-- TABLE ROW : topic groups -->
+| style="vertical-align: top;" |
-[[nn_linux_software_package_notes|Linux software package notes]] a separate wiki document on Neela wiki.  - TMH
+<ul><!-- TOPIC GROUP NAME "Documentation" -->
+<li> [https://www.nasa.gov/seh/appendix-c-how-to-write-a-good-requirement NASA Requirements How-To]
+<li> [[Presentation_tools|presentation tools]]
+<li> [[doxygen_notes|Doxygen notes]]
+<li> [[rst|Restructured Text (rst)]]
+</ul>
+| style="vertical-align: top;" |
+<ul><!-- TOPIC GROUP NAME "Programming languages" -->
+<li> [[assembly_language|assembly]]
+<li> [[C_programming_notes|C]]
+<li> [[Device_tree|Device Tree and dts]]
+<li> [[Kconfig|Kconfig]]
+<li> [[shell|shell]]
+</ul>
-<!-- comment -->
+| style="vertical-align: top;" |
-== - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - - ==
+<ul><!-- TOPIC GROUP NAME "Programming languages" -->
+<li> [https://ada-lang.io/ Ada]
+<li> [https://www.rust-lang.org/ Rust]
+<li> [https://inko-lang.org/ Inko]
+<li> [[Python_notes|Python notes]]
+<li> [[Perl|Perl]]
+</ul>
+| style="vertical-align: top;" |
+<ul><!-- TOPIC GROUP NAME "Data Integrity" -->
+<li> [[data_integrity_methods|data integrity methods]]
+<li> [[programming_constructs|programming constructs]]
+</ul>
-<!-- comment -->
+|} <!-- CLOSE OF WIKI TABLE -->
-<!-- SECTION - Bash Shell Scripting -->
+<!--
+==== <i>edit point </i> ====
+-->
+{| class="wikitable"
-== [[#top|&uarr;]] [[#references|&darr;]] Bash Shell Scripting ==
+|- <!-- TABLE ROW : topic group ids -->
+! scope="col" style="min-width: 250px; width: 20%;" | 9
+! scope="col" style="min-width: 250px; width: 20%;" | 10
+! scope="col" style="min-width: 250px; width: 20%;" | 11
+! scope="col" style="min-width: 250px; width: 20%;" | 12
+|- <!-- TABLE ROW : topic group names -->
+! scope="col" style="min-width: 250px; width: 20%;" | Technologies
+! scope="col" style="min-width: 250px; width: 20%;" | Local works
+! scope="col" style="min-width: 250px; width: 20%;" | Local works
+! scope="col" style="min-width: 250px; width: 20%;" | Code Libraries
-Bash (Bourne shell) Quick Reference:
+|- <!-- TABLE ROW : topic groups -->
+| style="vertical-align: top;" |
-<pre>
+<ul><!-- TOPIC GROUP 9 NAME "Technologies" -->
-Shell Built-in Variables:
-   $0    Name of given shell script itself
+<li> [https://cartesiam-neai-docs.readthedocs-hosted.com/ Cartesiam]
-   $1    Value of first command line parameter (similarly $2, $3, ...)
+<li> [https://cartesiam-neai-docs.readthedocs-hosted.com/studio/studio.html#ii-project-creation Cartesiam AI Studio]
-   $#    In given shell script the number of command line parameters received
+<li> [[cybersecurity|security topics]]
-   $*    All of the command line parameters
+<li> [[wireless_communications|Wireless communications]]
-   $-    Options given to the shell
+</ul>
-   $?    Return (or holds) the exit status of the last command
-   $$    Process id of given script (really the id of the shell running the script)
+| style="vertical-align: top;" |
-Shell test constructs:
+<ul><!-- TOPIC GROUP 10 NAME "Local works" -->
-SYNTAX      NAME OF SHELL TEST                                NOTES
+<li>[[zephyr_building_blocks|Zephyr building blocks <font size=1>reference</font>]]<br />
+^^^ <i>NEEDS ORGANIZATION</i> ^^^
-[           built-in test                                     considers its arguments as comparison expressions or file tests
+<li>[[zephyr_device_driver_model|Zephyr device drivers, Jared Wolff<font size=1>study</font>]] <font size="1"><span style="background:#e6ffcc;>&nbsp;</span><span style="background:#ffffcc;>&nbsp;</span><span style="background:#ffe6cc;>&nbsp;</span><span style="background:#ffb3b3;>&nbsp;</span></font><br />
+<li>[https://github.com/tedhavelka/kionix-driver-demo Zephyr driver demo]
+<li>[[nrf_modem_library_notes|nRF modem lib <font size=1>study</font>]]
+<!-- vi /home/cpguest/embedded/ncs/v1.6.1/nrf/lib/nrf_modem_lib/nrf_modem_lib.c -->
+<li>[[spi_device_tree_source_code|SPI device tree source code]]
+<li> [[Pico-sdk_studies|RPi Pico SDK studies]]
+<li> [[Firmware_goals|firmware goals]]
+</ul>
-[[...]]     in Bash => 2.02 the extended test command
+| style="vertical-align: top;" |
-((...))     arithmetic tests                                  example:  (( 0 && 1 ))  # Logical AND
+<ul><!-- TOPIC GROUP 11 NAME "Local works" -->
+<li>[[nrf_sample_app_aws_iot|sample aws_oit <font size=1>study</font>]]<br />
+<li>[[zephyr_rtos_threads|Zephyr RTOS threads <font size=1> </font>]]<br />
+<li>[[zephyr_in_tree_driver_use|In-tree driver]]<br />
+<li>[[iis2dh|ST Micro IIS2DH]]<br />
+<li>[[zephyr_board_porting|Zephyr board porting]]<br />
+<li>[[i2c_driver_notes|I2C driver notes]]
+</ul>
-</pre>
+| style="vertical-align: top;" |
-<i>
+<ul><!-- TOPIC GROUP 12 NAME "Code libraries" -->
-Reference:  http://tldp.org/LDP/abs/html/testconstructs.html
-</i>
+<li> [[Nordicsemi-software-development-kit|Nordic nrf-sdk]]
+<li> [[Zephyr-sdk-install-and-config|Zephyr SDK installation notes]]
+<li> [[CMSIS_notes|CMSIS notes]]
+<li> [[curl_notes|libcurl notes]]
+<li> [[MCUXpresso_SDK|MCUXpresso SDK]]
+<li> [[NXP_HAL|NXP LPC HAL]]
+</ul>
+|} <!-- CLOSE OF WIKI TABLE -->
+<!--
+|-
+| scope="col" style="min-width: 250px; max-width: 300px; column-span:4;" |
+==== <i>edit point</i> ====
+-->
+{| class="wikitable"
-Shell scripting and use of built-in shell commands is a practical knowledge to employ, when working in Unix-like environments.  One common task is to find all the instances of a given file or program.  The <code>locate</code> command can perform this kind of search, but it's results don't show whether the file instances differ.  To check at the rough level of file size, we can use a one-line shell script technique involving shell piping, to "long list" the results of the <code>locate</code> command, like this . . .
+|- <!-- TABLE ROW : topic group ids -->
+! scope="col" style="min-width: 250px; width: 20%;" | 13
+! scope="col" style="min-width: 250px; width: 20%;" | 14
+! scope="col" style="min-width: 250px; width: 20%;" | 15
+! scope="col" style="min-width: 250px; width: 20%;" | 16
-<pre>
+|-  <!-- TABLE ROW : topic group names -->
-  $ for file in `locate tavrasm | grep 'asm$'`; do ls -l ${file}; done
+! scope="col" style="min-width: 250px; max-width: 300px;" | Open software projects
-</pre>
+! scope="col" style="min-width: 250px; max-width: 300px;" | Comms protocols
+! scope="col" style="min-width: 250px; max-width: 300px;" | Encodings
+! scope="col" style="min-width: 250px; max-width: 300px;" | Hardware issues
-Hmm strange, the above command calls `grep` with a pattern that ends in the shell end-of-line anchoring character $, and appears to filter for results of `locate` which end in 'asm'.  But on 2017-09-12 needed to add a "one or more wildcard" character pattern to limit search results for instances of `locate` results ending in 'qemu':
+|- <!-- TABLE ROW : topic groups -->
+| style="vertical-align: top;" |
-<pre>
+<ul><!-- TOPIC GROUP NAME "open software projects" -->
-$ locate qemu | grep '.*qemu$'
+<li>  [https://github.com/apache/httpd/tree/trunk Apache2 webserver]
-</pre>
+<li>  [https://www.mcuboot.com/about/ MCUBoot open governance]
+</ul>
-Why the apparent difference in command invocation?  Need to test . . .  - TMH
+| style="vertical-align: top;" |
+<ul><!-- TOPIC GROUP NAME "comms protocols" -->
+<li>  [[i2c|I2C]]
+<li>  [https://learn.sparkfun.com/tutorials/serial-peripheral-interface-spi/all SPI Sparkfun tutorial]
+<li>  [[protocol_SPI|SPI]]
+<li>  [https://infocenter.nordicsemi.com/pdf/nrf91_at_commands_v1.2.pdf AT commands]
+<li>  [[lte_at_command_notes|LTE AT command notes]]
+<li>  [https://www.hivemq.com/blog/mqtt-essentials-part2-publish-subscribe/ MQTT 2/10 intro series]
+<li>  [[mqtt_notes|MQTT notes]]
+<li>  [[swd|notes serial wire debug SWD]]
+<li>  [[bootloading|notes serial bootloading]]
+<li>  [[CAN|CAN]]
+</ul>
+| style="vertical-align: top;" |
-Command to break out first ten $PATH environment variable to individual paths each shown on a line of the shell:
+<ul><!-- TOPIC GROUP NAME "encodings" -->
+<li>  [[json|JSON notes]] <!-- [https://www.w3schools.com/whatis/whatis_json.asp JSON] -->
+<li>  [https://www.tutorialspoint.com/protobuf/index.htm Protobuf]
+<li>  [[protobuf_notes|Protobuf notes]]
+<li>  [[intel_hex_format|Intel hex format]]
+<li>  [[ASCII|ASCII]]
+<li>  [[cbor|cbor notes]]
+</ul>
-<pre>
+| style="vertical-align: top;" |
-for path in `echo $PATH | cut -d':' -f1-10 --output-delimiter=' '`; do echo $path; done
-</pre>
+<ul><!-- TOPIC GROUP NAME "Hardware" -->
+<li> [[hardware_studies_specific|specific hardware studies]]
+<li> [[video_games|Classic video games]]
+</ul>
+|} <!-- CLOSE OF WIKI TABLE -->
+<!--
+|-
+| scope="col" style="min-width: 250px; max-width: 300px; column-span:4;" |
+==== <i>edit point</i> ====
+-->
+{| class="wikitable"
-=== <i> [[#top|&uarr;]] [[#references|&darr;]] edit point - shell variable quoting</i> ===
+|- <!-- TABLE ROW : topic group ids -->
+! scope="col" style="min-width: 250px; width: 20%;" | 17
+! scope="col" style="min-width: 250px; width: 20%;" | 18
+! scope="col" style="min-width: 250px; width: 20%;" | 19
+! scope="col" style="min-width: 250px; width: 20%;" | 20
-- 2017-10-19 THU -
+|- <!-- TABLE ROW : topic group names -->
+! scope="col" style="min-width: 250px; max-width: 300px;" | Local stuff
+! scope="col" style="min-width: 250px; max-width: 300px;" | Academic
+! scope="col" style="min-width: 250px; max-width: 300px;" | Cloud based services
+! scope="col" style="min-width: 250px; max-width: 300px;" | Interesting projects
-Running into issues when need to expand shell variable in single quotes pair . . .
+|- <!-- TABLE ROW : topic groups -->
+| style="vertical-align: top;" |
-[https://unix.stackexchange.com/questions/178411/how-to-use-variables-inside-single-quotes Stack Exchange, Unix forum post 178411]<br />
+<ul><!-- TOPIC GROUP NAME "" -->
-[http://tldp.org/LDP/abs/html/varassignment.html TLPD Advanced Bash Scripting Guide, chapter 4.2 example 4-3 double quotes preserve white space]<br />
+<li>  [[bulletin-board|NN bulletin board]]
+<li>  [[terminology|Terminology pages]]
+<li>  [[to-do|TO DO]]
+<li>  [[Bash_start_up_script|bookmarker]]
+</ul>
-WIKI WISH LIST - While adding to wiki, Ted noting that would be useful to have relative-depth wiki section markers.  The standard wiki section markers '== ==', '=== ===' and similar have fixed depth.  That is, '== ==' is always a top-level or first-level section in a wiki document, '=== ===' is always a sub-subsection of wiki documents, and '==== ====' a sub-sub-section.  When section gets re-factored into its own article, would be handy to have those section markers rise up to levels of top-most and successive section markers.  - TMH
+| style="vertical-align: top;" |
+<ul><!-- TOPIC GROUP NAME "" -->
+ [[ece-reference-materials|ECE reference materials]]
+</ul>
-<!-- comment -->
+| style="vertical-align: top;" |
-=== [[#top|&uarr;]] [[#references|&darr;]] example shell script - back up several databases ===
+<ul><!-- TOPIC GROUP NAME "" -->
-&nbsp;<br />
+<li>  [https://hub.docker.com/ Docker Hub site]
-Here is a simple shell script to call mysqldump utility and back up several databases.  Couple of things Ted wants to add to this script include script variables to hold back-up filename prefix and infix patterns, and an option to compress the MYSQL dump files . . .
+<li>  [https://bifravst.github.io/bifravst/docs/aws/GettingStarted.html bifravst]
+<li>  [https://docs.aws.amazon.com/AmazonS3/latest/userguide/Versioning.html Amazon S3 versioning]
+<li>  [[AWS_notes|AWS notes]]
+<li>  [[character_sequences|CLI and character sequences]]
+<li>  [https://www.ntppool.org/en/ NTP Pool organization]
+</ul>
-<i>Figure x - shell script to back-up multiple MYSQL databases</i>
+| style="vertical-align: top;" |
-<pre>
+<ul><!-- TOPIC GROUP NAME "Interesting projects" -->
-#!/bin/bash
+<li> [https://devzone.nordicsemi.com/nordic/nrf-connect-sdk-guides/b/software/posts/enter-the-multi-nus-a-simple-wireless-uart-network nRF multi-NUS]
+<li> [https://docs.zephyrproject.org/latest/samples/drivers/led_ws2812/README.html WS2812 Zephyr driver]
+<li> [https://github.com/EseyeIoT/EseyeTelemetryModule-STM32_library Eseye IoT telem STM32]
+</ul>
+|} <!-- CLOSE OF WIKI TABLE -->
-DATABASE_LIST="information_schema mysql drupal_8p0 phpmyadmin wiki_database"
+== [[#top|^]] temporary section ==
-user="root"
+Note:  useful to add ratings of completeness and organization to above links that point to local wiki pages.
-pass_phrase_for_mysql="mysql_user_password"
-options_extra="--skip-lock-tables"
-response="n"
+*  https://devzone.nordicsemi.com/nordic/cellular-iot-guides/b/software-and-protocols/posts/connecting-to-aws-cloud-services-using-the-nrf9160
-mode_interactive="n"
+*  https://community.helium.com/t/new-to-helium-start-here/80
+http://iotfactory.eu/lorawan-world-frequency-map-lora-sigfox-nbiot-telecom-operators-per-country/  LoRaWAN world frequency map (not exhaustive)
+Always useful to review, wiki table syntax help:
+  *  [https://en.wikipedia.org/wiki/Help:Table wiki table help]
+<!-- comment -->
-echo "shell script starting,"
+Wiki-driven table of contents here:
+__TOC__
-for database in ${DATABASE_LIST};
-do echo "backing up alta-ubuntu database $database . . .";
-#    command="mysqldump --databases $database -u$user -p$pass_phrase_for_mysql $options_extra >> au-database-back-up--${database}.sql"
+<!-- SECTION - Countries and Politics -->
-    command="mysqldump --databases $database -u$user -p$pass_phrase_for_mysql $options_extra"
-    redirect="au-database-back-up--${database}.sql"
-    if [ $mode_interactive = 'y' ]; then
+=== [[#top|&uarr;]] [[#references|&darr;]] <i> Countries and politics </i> ===
-        echo "build command '$command' and database back-up filename'$redirect',"
+*  https://www.nytimes.com/2018/07/28/world/americas/china-latin-america.html
-        echo "full command will be '$command' > '$redirect',"
-        echo "trying running this command and redirect? [y/N/q]  yes, no, 'q' to quit"
-        read response
-        if [ $response = 'Y' -o $response = 'y' ]; then
-            ${command} > $redirect
-        elif [ $response = 'N' -o $response = 'n' ]; then
-            echo "skipping present command . . ."
-        elif [ $response = 'Q' -o $response = 'q' ]; then
-            echo "stopping script '$0' and exiting."
-            break
-        fi
-        echo
-    else
-        echo "$0:  backing up database '$database' to file '$redirect' . . ."
+<!-- comment -->
-        ${command} > $redirect
-        ls -l $redirect
+<!-- SECTION - Community, Culture, the World -->
-    fi
+== [[#top|&uarr;]] [[#references|&darr;]]<!--[[new_page|&darr;]]--> Community, Culture, the World ==
-done
+Following sections on Community, Geography, Culture, Musica and the world may become a separate wiki page in the future.
-echo "done."
+<!-- comment -->
-exit 0
+=== [[#top|&uarr;]] [[#references|&darr;]] Geography and Place ===
-</pre>
-=== [[#top|&uarr;]] [[#references|&darr;]] show kernel version script ===
+*  https://www.usatoday.com/border-wall/story/flight-over-entire-us-mexico-border-fence/605855001/
-Following script 'showkversion' can be used in a Linux kernel source tree to determine the kernel's version number, based on the number elements defined in the kernel's top level makefile.
+*  Morocco weather climate and agriculture . . .
+**  [http://www.our-africa.org/morocco/climate-agriculture Morocco's climate - Our Africa site]
+**  http://www.essaouira.nu/ecology_climate.htm
+**  http://www.worldbank.org/en/news/feature/2015/11/23/green-growth-putting-morocco-in-the-lead-against-climate-change
-<i>Figure x - simple bash script to show kernel version in root of kernel sources tree</i>
+*  [https://www.sesptsa.org/featured/2018-tree-recycling/ Southeast Environmental School PTSA]
-<pre>
+*  [http://www.lensjoy.com/gallery/20.htm Tsagaglalal 'She Who Watches']
-#!/bin/bash
+<!--
+*  https://workbasedlearning.pnnl.gov/pals/resource/cards/bunchgrass.stm
+*  http://calscape.org/Festuca-idahoensis-(Idaho-Fescue) . . . includes mention of purple needlegrass
+*  https://en.wikipedia.org/wiki/Nassella_pulchra
+   *  https://en.wikipedia.org/wiki/List_of_California_native_plants#Common_grasses
+   *  https://en.wikipedia.org/wiki/Category:Native_grasses_of_California
+   *
+-->
-## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-## Started 2017-12-15 FRI - script to parse and show Linux kernel
-##  version from top-level makefile in set of kernel sources.  Patterns
-##  to `grep` chosen based on kernel version identifiers in first
-##  three lines of typical kernel top-level makefile.  Example:
-##
-##  $ head -n 6 Makefile
-##  VERSION = 4
-##  PATCHLEVEL = 9
-##  SUBLEVEL = 66
-##  EXTRAVERSION =
-##  NAME = Roaring Lionus
-##
-##
-## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+*  https://lebanonuntravelled.com/iris-sofarana-endemic-lebanese-flower/  Iris sofarana endemic to Lebanon
-script_name="showkversion"
+<!-- comment -->
-if [ ]; then
+=== [[#top|&uarr;]] [[#references|&darr;]] People ===
-    head -n 5 Makefile | grep ^VERSION | cut -d " " -f 3
-    head -n 5 Makefile | grep ^PATCH | cut -d " " -f 3
-    head -n 5 Makefile | grep ^SUBLEVEL | cut -d " " -f 3
-fi
-MAJOR=$(head -n 5 Makefile | grep ^VERSION | cut -d " " -f 3)
+Cultural and envinrmental:
-MINOR1=$(head -n 5 Makefile | grep ^PATCH | cut -d " " -f 3)
+<ul>
-MINOR2=$(head -n 5 Makefile | grep ^SUBLEVEL | cut -d " " -f 3)
+*  https://www.hcn.org/issues/51.6/tribal-affairs-in-california-the-karuk-tribe-fights-a-growing-wildfire-threat-and-a-lack-of-funding
+</ul>
-KERNEL_REVISION="${MAJOR}.${MINOR1}.${MINOR2}"
-echo
+*  https://www.opb.org/radio/programs/bbc-outlook/
-echo "Kernel version in present kernel sources tree, per makefile, is ${KERNEL_REVISION}"
+<ul>
-echo
+*  https://www.bbc.co.uk/programmes/w3cswsmc
+*  https://www.cnn.com/style/article/italy-umbrella-maker-talarico/index.html
+</ul>
+Encontrado 2019-12-30 lunes, commentario sobre Mahatma Gandhi:
+<ul>
+*  https://www.kolorkomplex.com/kolorkomplex-culture/2017/1/4/mahatma-gandhi
+</ul>
-exit 0
-</pre>
+Tech authors, astronomy, more Linux reference material:
+<ul>
+*  https://www.howtogeek.com/author/lorikaufman/
+*  https://www.theatlantic.com/science/archive/2017/05/aliens-on-your-packard-bell/527445/
+</ul>
 <!-- comment -->
-=== [[#top|&uarr;]] [[#references|&darr;]] Other useful shell tutorial references ===
+=== [[#top|&uarr;]] [[#references|&darr;]] Human languages ===
-*  http://tldp.org/LDP/abs/html/textproc.html . . . commands cut, paste, join and others
+*  [[nn-english-hindi-glossary|English-Hindi glossary at NN]]
-*  https://unix.stackexchange.com/questions/131766/why-does-my-shell-script-choke-on-whitespace-or-other-special-characters . . . read shell input line by line
-*  https://stackoverflow.com/questions/7427262/how-to-read-a-file-into-a-variable-in-shell . . . read file into shell variable
+*  [https://www.omniglot.com/writing/devanagari_conjuncts.php Devanagari conjunct characters]
+*  [[cool_new_words|cool new words encountered . . .]]
-<!-- comment -->
+*  [https://www.pinterest.com/pin/836191855785684878/ US standard Braille and other symbol and language systems]
-== [[#top|&uarr;]] [[#references|&darr;]] Other Computer Programming Languages ==
+- 2017-12-15 FRI -
+*  https://etohautakuva.deviantart.com/art/Taugedei-Abugida-Alphasyllabary-Cheatsheet-610277914
+*  http://langventure.strikingly.com/blog/hindi-abugida-in-action
+*  https://wsotw.weebly.com/blog/alphabets-abugidas-and-syllabaries
+<!--
+Gaurav
+Gaurav
+months ago
+ओ पालनहारे निर्गुण और न्यारे
+ओ पालनहारे निर्गुण और न्यारे
+तुमरे बिन हमरा कौनों नहीं
+हमरी उलझन सुलझाओं भगवान
+तुमरे बिन हमरा कौनों नहीं
+तुम्हे हमका हो संभाले
+तुम्हे हमरे रखवाले
+तुमरे बिन हमरा कौनों नहीं
+तुमरे बिन हमरा कौनों नहीं
-<!-- comment -->
+चंदा में तुम्ह भरे हो चांदनी
+सूरज में उजाला तुम्ह से
+ये गगन है मगन
+तुम्हे तो दिए हो इससे तारे
+भगवान ये जीवन ना सवारोगे
+तो क्या कोई सवारे
+ओ पालनहारे निर्गुण और न्यारे
+तुमरे बिन हमरा कौनों नहीं
+तुमरे बिन हमरा कौनों नहीं
+जो सनों तो कहे प्रभुजी हमरी है बिनती
+दुखी हैं को धीरज दो
+हारे नहीं वो कभी दुख से
+तुम निर्बल को रक्षा के
+रेह पाए निर्बल सुख से
+भक्ति को शक्ति को
+भक्ति को शक्ति को
+जग के जो स्वामी हो
+इतनी तो अरज सुनो
+है पथ में अंधियारे
+देदो वरदान में उजियारे
+ओ पालनहारे निर्गुण और न्यारे
+तुमरे बिन हमरा कौनों नहीं
+हमरी उलझन सुलझाओं भगवान
+तुमरे बिन हमरा कौनों नहीं
-=== [[#top|&uarr;]] [[#references|&darr;]] Python Scripting Language ===
+ओ पालनहारे निर्गुण और न्यारे
+तुमरे बिन हमरा कौनों नहीं
+हमरी उलझन सुलझाओं भगवान
+तुमरे बिन हमरा कौनों नहीं
+-->
-*  https://docs.python.org/2/tutorial/index.html
+<!-- comment -->
-*  https://learn.onemonth.com/ruby-vs-python/
+=== [[#top|&uarr;]] [[#references|&darr;]] Science ===
+*  https://www.asbmb.org/asbmb-today/science/020721/a-brief-history-of-the-periodic-table
+*  https://en.wikipedia.org/wiki/List_of_elements_by_stability_of_isotopes
+== - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - - ==
 <!-- comment -->
-=== [[#top|&uarr;]] [[#references|&darr;]] Expect Utility by Don Libes ===
+- 2017-10-05 - Ted noting here that would be good to have a [[technical_glossary|technical glossary]] to make easily accessible all the technical terms which arise in daily work and exploration of technologies . . .
-*  https://www.unix.com/shell-programming-and-scripting/176054-multiple-while-loops-expect-script.html?s=3aa3009c43b2e834326eea6dfa0d1139
-Good short examples covering range of tasks here at Robert Elder blog page, noting md5sum expect script example . . .
+- 2017-10-19 - TO-DO list:
-*  http://blog.robertelder.org/don-libes-expect-unix-automation-tool/
-*  https://www.ibm.com/developerworks/community/blogs/brian/entry/when_to_use_expect_scripting_and_when_to_avoid_it10?lang=en Expect script with while-loop
+   *  [&#10003;] complete LFS 8.1 exercise
+   *  [ ] configure xserver to run stand-along without window manager (seems to be working on 1604 spare LTS host . . .)
+   *  [ ] set up two mysql servers on one host
+   *  [ ] write "best photo contribution" practices page for ASI
+   *  [ ] code "re-use or reference text block" module for MediaWiki <i> &lt;-- this needs further explanation - TMH </i>
+   *  [ ] in local Neela Nurseries PHP code base, amend hybrid building of nav menus to include highlighting parent page of given viewed page
+   *  [ ] in OpenCart 2.x find way to customize top-of-page information and links
+   *  [ ] in OpenCart 2.x find way to format product lists as compact lists, like Gmail inbox or Windows 'list view' of files
-*  https://wiki.tcl.tk/11584 list of Expect tutorials
-*  https://debaan.blogspot.com/2007/09/simple-expect-ssh-example.html
+<!-- comment -->
-*  http://wiki.tcl.tk/11583
+== [[#top|&uarr;]] [[#references|&darr;]] GNU Make and GCC Tools ==
-How to capture specific results during an expect script's execution:
+<br />
-*  https://stackoverflow.com/questions/2077721/how-do-you-save-and-parse-a-command-output-in-expect
+<span style="background-color:#ffd0d0; border:maroon 1px dotted; padding:10px;"><i>2018-07-18 NOTE:  this section to be moved to separate [[Make_and_GCC|GCC and Make article]] . . .  - TMH</i></span>
+<br />
-- 2018-01-30 - Tuesday, picking up from last week researching how to redirect expect output and its spawned processes' output with filtering to log file.  The first reference here at Stackoverflow repeats the useful <code>lindex</code> syntax.  There is also mention of the <code>expect</code> manual and a syntax <code>$::env(action)</code> which can be expressed in an expect script to access an environment variable that is part of the controlling shell . . .
+*  https://gcc.gnu.org/onlinedocs/gcc-8.4.0/cpp/Stringizing.html
-*  https://stackoverflow.com/questions/11131318/how-to-use-bash-script-variables-in-expect-conditional-statements
-How to use expect's <code>log_file</code> key word in an expect script:
+*  https://www.gnu.org/software/make/manual/html_node/Special-Targets.html
-*  https://stackoverflow.com/questions/15965504/how-to-create-log-file-for-tcl-script
-From the manual page for expect version 5.45:
+Using macros with gcc:
+*  https://gcc.gnu.org/onlinedocs/gcc/Option-Summary.html   . . . gcc summary of options
+*  https://gcc.gnu.org/onlinedocs/cpp/Macros.html           . . . defining macros with -Dmacro_name=expression
+*  https://gcc.gnu.org/onlinedocs/gcc/Preprocessor-Options.html#Preprocessor-Options   . . . -MT and other preprocessor options
-<ul>
+Code libraries and shared objects, expressing paths to them:
-<i>
+*  https://gist.github.com/gubatron/32f82053596c24b6bec6
-<pre>
-       log_file [args] [[-a] file]
-             If a filename is provided, log_file will record a transcript of the session (beginning at that point) in
-             the file.  log_file will stop recording if no argument is given.  Any previous log file is closed.
-             Instead  of  a  filename,  a Tcl file identifier may be provided by using the -open or -leaveopen flags.
+gcc.gnu.org - 3.15 Specifying subprocesses and switches passed to them
-             This is similar to the spawn command.  (See spawn for more info.)
+*  https://gcc.gnu.org/onlinedocs/gcc-4.1.2/gcc/Spec-Files.html#Spec-Files
-             The -a flag forces output to be logged that was suppressed by the log_user command.
+gcc how to show macros and pre-processor defines:
+*  https://stackoverflow.com/questions/2224334/gcc-dump-preprocessor-defines
-             By default, the log_file command appends to old files rather than truncating them, for  the  convenience
-             of  being  able  to  turn  logging off and on multiple times in one session.  To truncate files, use the
-             -noappend flag.
-             The -info flag causes log_file to return a description of the most recent non-info arguments given.
+<!-- comment -->
-</pre>
-</i>
-</ul>
+== [[#top|&uarr;]] [[#references|&darr;]] OpenOCD and Eagle set up notes ==
-Also from the expect manual page, Expect Hints section:
+Eagle fails to start due to symbols not resolve-able . . .
+  *  https://forums.autodesk.com/t5/eagle-forum/can-t-run-eagle-on-debian-10-testing/td-p/8312348
-<ul>
+Automake or autoconf or autoreconf -i fails for LIBTOOL undefined . . .
-<i>
-<pre>
-EXPECT HINTS
-       There are a couple of things about Expect that may be non-intuitive.  This section attempts to address some of
-       these things with a couple of suggestions.
-       A common expect problem is how to recognize shell prompts.  Since these are customized differently by  differ-
+  *  https://stackoverflow.com/questions/18978252/error-libtool-library-used-but-libtool-is-undefined
-       ently  people and different shells, portably automating rlogin can be difficult without knowing the prompt.  A
-       reasonable convention is to have users store a regular expression describing their prompt (in particular,  the
-       end  of it) in the environment variable EXPECT_PROMPT.  Code like the following can be used.  If EXPECT_PROMPT
-       doesn't exist, the code still has a good chance of functioning correctly.
-           set prompt "(%|#|\\$) $"          ;# default prompt
-           catch {set prompt $env(EXPECT_PROMPT)}
-           expect -re $prompt
-       I encourage you to write expect patterns that include the end of whatever you expect to see.  This avoids  the
+  *  https://stackoverflow.com/questions/43565009/failing-to-enable-stlink-in-openocd
-       possibility  of  answering a question before seeing the entire thing.  In addition . . .
-</pre>
-</i>
-</ul>
+<!-- comment -->
-The expect program has some built-in string buffers, and one of these may hold the latest characters received from a spawned process.  Here is a man page excerpt which shows use of one of these expect buffers:
+<!-- SECTION - Mediawiki Issues and Notes -->
+== [[#top|&uarr;]] [[#references|&darr;]] Mediawiki Issues and Notes ==
+- 2018-01-22 -
+While editing sidebar of Mediawiki instance at Neela, Ted noticing a difference in Mediawiki's treatment of hyperlinks in the sidebar.  Links to external sites don't appear, and links to internal pages require single square brace enclosure to appear with alternate text as a link label . . .
-<ul>
-<i>
 <pre>
-       disconnect
+<!--
-             disconnects a forked process from the terminal.  It continues running in the background.  The process is
+** [https://buildroot.org/downloads/manual/manual.html Buildroot manual]
-             given its own process group (if possible).  Standard I/O is redirected to /dev/null.
+<a href="https://buildroot.org/downloads/manual/manual.html">Buildroot manual</a>
+- 2018-01-22 MON -
+** https://wiki.neelanurseries.com/index.php/Nn_embedded_linux_notes#.E2.86.91_.E2.86.93_Buildroot|Buildroot notes . . . only 'notes' shows as non-link text - TMH
+-->
+</pre>
-             The following fragment uses disconnect to continue running the script in the background.
+=== [[#top|^]] File uploads ===
-                 if {[fork]!=0} exit
+- 2018-06-29 FRI -
-                 disconnect
+Issue adding .txt type files to whitelist of Mediawiki installation uploadable files:
-                 . . .
-             The following script reads a password, and then runs a program every hour that demands a  password  each
+<pre>
-             time  it is run.  The script supplies the password so that you only have to type it once.  (See the stty
+Action failed
-             command which demonstrates how to turn off password echoing.)
-                 send_user "password?\ "
+Could not open lock file for "mwstore://local-backend/local-public/e/ec/Asi-officers-list-2018.txt".
-                 expect_user -re "(.*)\n"
-                 for {} 1 {} {
+Return to Main Page.
-                     if {[fork]!=0} {sleep 3600;continue}
-                     disconnect
-                     spawn priv_prog
-                     expect Password:
-                     send "$expect_out(1,string)\r"
-                     . . .
-                     exit
-                 }
 </pre>
-</i>
-</ul>
+[[media:arrow-up-prelight.png|200px|thumb|left|png type image]] to test file uploads of allowed image type . . .<br />
+[[media:arrow-up-prelight.png]]
-Further looking for expect's built-in string buffers and variables . . .
-*  http://wiki.tcl.tk/17378
+Following link may have helpful information:
-Pattern matching syntax in Don Libe's expect . . .
+*  https://www.mediawiki.org/wiki/Topic:Qlib7k3p2zvi7pkq
-*  http://www.embecosm.com/appnotes/ean8/html/ch03s02s01.html
+- 2018-07-25 WED -
-*  https://www.pantz.org/software/expect/expect_examples_and_tips.html . . . some timing stuff and <b>expect script blocks</b>
+*  https://www.mediawiki.org/wiki/Manual:Configuring_file_uploads   . . . be sure to examine $wgFileBlacklist in addition to $wgFileExtensions,
-*  http://www.asic-world.com/scripting/tcl3.html . . . regex in Tcl must enclose pattern in braces.
+<!-- comment -->
+=== [[#top|^]] Images in wiki pages and image attributes ===
+*  https://en.wikipedia.org/wiki/Wikipedia:Images_linking_to_articles
-From another source, Tcl's string match command:
+<!-- comment -->
- if [string match "f*b*" "foobar"] {
+=== [[#top|^]] Mediawiki layout topics like multi column layout ===
-    puts "match"
- else {
-    puts "no match"
- }
+- 2018-11-30 FRI -
+*  https://www.mediawiki.org/wiki/Topic:Ube2zt7nhfk51l3s
 <!-- comment -->
-=== <i>[[#top|&uarr;]] [[#references|&darr;]] edit point - Tool command language Tcl </i> ===
+=== [[#top|^]] Other Mediawiki topics ===
+*  https://www.mediawiki.org/wiki/Help:Moving_a_page
-<pre>
+<!-- comment -->
-"Practical programming
-in Tcl and Tk"
-ISBN 0-13-038560-3
-</pre>
+<!-- SECTION - Web Site Building Blocks -->
-In using Don Libes' <code>expect</code> utility or program, looks like it will be important and helpful to understand Tool Command Language Tcl to at least some fluency.  Here appears to be a good starting point tutorial for Tcl:
+== [[#top|&uarr;]] [[#references|&darr;]] Web Site Building Blocks - Summer 2017 to 2020 Q1 Work ==
-*  https://www.tutorialspoint.com/tcl-tk/tcl_commands.htm
+Must begin a new section on web site security issues.  Here are a couple of articles as starting points to sleuth out how the "WARNING - Please read me XMG" ransomeware attack can reach MYSQL databases of on-line hosts:
+<ul>
+*  https://www.wordfence.com/blog/2017/07/searchreplacedb2-security/.
+*  https://www.imperva.com/blog/ransomware-attacks-on-mysql-and-mongodb/
+</ul>
-Tcl <code>puts</code> built-in command, channels and code to open log file,
-*  https://www.tcl.tk/man/tcl8.4/TclCmd/puts.htm
-<pre>
+-11-12
-Append a log message to a file:
+<ul>
+*  https://dev.mysql.com/doc/refman/5.7/en/server-logs.html
+*  https://www.percona.com/blog/2012/12/28/auditing-login-attempts-in-mysql/
+</ul>
-set chan [open my.log a]
-set timestamp [clock format [clock seconds]]
-puts $chan "$timestamp - Hello, World!"
-close $chan
-</pre>
+* [[nn_web_site_building_blocks|Web site building blocks]] . . . now a separate wiki document, as of 2018-01-08.  - TMH
-Tcl regular expressions:
+-01-27 htpasswd access files
+<ul>
+*  https://www.htaccesstools.com/articles/htpasswd/
+</ul>
-*  https://www.tcl.tk/man/tcl8.2.3/TclCmd/re_syntax.htm
+<!-- comment -->
-Tcl reserved words:
+== [[#top|&uarr;]] [[#references|&darr;]] Open Source License Types ==
-<pre>
-after		append		array		auto_execok
-auto_import	auto_load	auto_load_index	auto_qualify
-binary		Bgerror		break		catch
-cd		Clock		close		concat
-continue	Dde		default		else
-elseif		Encoding	eof		error
-eval		Exec		exit		expr
-fblocked	Fconfigure	fcopy		file
-fileevent	Flush		for		foreach
-format		Gets		glob		global
-history		If		info		interp
-join		Lappend		lindex		linsert
-list		Llength		load		lrange
-lreplace	Lsearch		lsort		namespace
-open		Package		pid		pkg_mkIndex
-proc		Puts		pwd		read
-regexp		Regsub		rename		resource
-return		Scan		seek		set
-socket		Source		split		string
-subst		Switch		tclLog		tell
-time		Trace		unknown		unset
-update		Uplevel		upvar		variable
-vwait		While
-</pre>
+*  https://lukasa.co.uk/2012/05/GPL_vs_MIT_Which_License_To_Use/
 <!-- comment -->
-=== <i>[[#top|&uarr;]] [[#references|&darr;]]edit point - Tcl pattern matching and anchoring, symbols ^ and $ wrt data not lines</i> ===
+<!-- SECTION - Linux packages -->
+== [[#top|&uarr;]] [[#references|&darr;]] Linux Packages (Separate Article) ==
-From the Tcl manual page on-line here is a clue about pattern matching in Tcl scripts, which may explain why we are struggling to obtain matched substrings from sequences of bytes from expect-spawned processes . . .
+[[nn_linux_software_package_notes|Linux software package notes]] a separate wiki document on Neela wiki.  - TMH
-<ul>
-<i>
-<pre>
-    Note that in many editors, the ^ and $ match the beginning and end of lines respectively. However, because expect is not line oriented, these characters match the beginning and end of the data (as opposed to lines) currently in the expect matching buffer. (Also, see the note below on "system indigestion.")
-</pre>
-</i>
-</ul>
+<!-- comment -->
+== - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - - ==
-Tcl regular expression syntax:
-*  https://www.tcl.tk/man/tcl8.2.3/TclCmd/re_syntax.htm#M57
+<!-- comment -->
-Expect variables, using global and upvar keywords in Tcl scripts:
+<!-- SECTION - Bash Shell Scripting -->
-*  http://www.huecker.com/msw/tcl/tutorial/Tcl13.shtml
+== [[#top|&uarr;]] [[#references|&darr;]] Bash Shell Scripting ==
-Excerpt on Tcl pattern matching from Inguza web site:
+Bash (Bourne shell) Quick Reference:
 <pre>
-   Expect
+Shell Built-in Variables:
-The expect suite actually consist just of a few commands: expect, send, spawn and interact and is an extension to TCL.
-Before the expect command can be used a program must be spawned, see expect commands below.
+   $0    Name of given shell script itself
-expect \
+   $1    Value of first command line parameter (similarly $2, $3, ...)
-  {match1} {action1} \
+   $#    In given shell script the number of command line parameters received
-  {match2} {action2} \
+   $*    All of the command line parameters
-  {match3} {action3} \
+   $-    Options given to the shell
-  {match4} {action4}
+   $?    Return (or holds) the exit status of the last command
-It is possible that no such output is encountered within the time period defined by the timeout (variable name "timeout" in seconds, default to 2). In this case expect stops waiting and continues with the next command in the script.
+   $$    Process id of given script (really the id of the shell running the script)
-You can use '*' to match any characters. You can also match using [] syntax and similar.
-expect "\[a-f0-9]"  ; # strongly preferred as \n and similar is not taken as litteral charactesr \ and n.
-expect {a-f0-9}     ; # can also be used
+Shell test constructs:
-A note on \ characters. The pattern matcher translate \x to x but this is done once before the pattern matcher. So you need to type \\n to match n. This is especially important for * and ? characters.
-expect "*" ;# match anything (*)
+SYNTAX      NAME OF SHELL TEST                                NOTES
-expect "\n" ;# match linefeed
-expect "\*" ;# match anything
+[           built-in test                                     considers its arguments as comparison expressions or file tests
-expect "\\*" ;# match * character
-expect "\\\*" ;# match * character
+[[...]]     in Bash => 2.02 the extended test command
-expect "\\\\*" ;# match \ followed by anything
-expect "\\\\\*" ;# match \ followed by anything
+((...))     arithmetic tests                                  example:  (( 0 && 1 ))  # Logical AND
-expect "\\\\\\*" ;# match \ followed * character
-The [ character is special to both tcl and the pattern matcher so it is especially messy.
-proc xy {} { return "n*w" }
+</pre>
-expect "[xy]" ;# match n followed by anything followed by w
-expect "\[xy]" ;# match x or y
+<i>
-expect "\\[xy]" ;# match n followed by anything followed by w
+References:
-expect "\\\[xy]" ;# match [xy]
+*  http://tldp.org/LDP/abs/html/testconstructs.html
-expect "\\\\[xy]" ;# match \ followed by n followed ...
+*  http://tldp.org/LDP/abs/html/internal.html#BUILTINREF
-expect "\\\\\[xy]" ;# match sequence of \ and then x or y.
+*  http://tldp.org/LDP/abs/html/string-manipulation.html
-The expect command can also take flags. The default flag is -gl for glob pattern matching. It can also take the flag -re for regular expression matching.
+</i>
-expect {
-  -re "a*" { action_when_a_followed_by_any_a }
-  "b*" { action_when_b_followed_by_anything }
-  -gl "-re" { action_when_real_dash_r_e }
+Shell scripting and use of built-in shell commands is a practical knowledge to employ, when working in Unix-like environments.  One common task is to find all the instances of a given file or program.  The <code>locate</code> command can perform this kind of search, but it's results don't show whether the file instances differ.  To check at the rough level of file size, we can use a one-line shell script technique involving shell piping, to "long list" the results of the <code>locate</code> command, like this . . .
-  eof { action_on_end_of_file }
-  timeout { action_on_command_timeout }
+<pre>
-  default { action_on_command_timeout_or_eof }
+   $ for file in `locate tavrasm | grep 'asm$'`; do ls -l ${file}; done
-  -re "(abc)*" { action_on_any_number_of_a_b_c }
+</pre>
-  -re "-?(0|\[1-9]\[0-9]*)?\\.?\[0-9]*" { action_on_float_or_integer }
-}
+Hmm strange, the above command calls `grep` with a pattern that ends in the shell end-of-line anchoring character $, and appears to filter for results of `locate` which end in 'asm'.  But on 2017-09-12 needed to add a "one or more wildcard" character pattern to limit search results for instances of `locate` results ending in 'qemu':
-You can also pass the pattern as a variable.
-set v2pats "pat2 act2"
+<pre>
-set v3pats "pat3 act3"
+    $ locate qemu | grep '.*qemu$'
-expect pat1 act1 $v2pats $v3pats
+</pre>
-Observe that the following expect string is wrong as $v2pats and $v3pats is considered as two different arguments. It will try to match $v2pats as a pattern and $v3pats as an action. Instead build up a string and use the -brace flag. You can not use double quotes for that though, unless you use eval and then the -brace flag is not necessary. You also need to protect the pattern and action inside a [list x] or an extra brace if they contain whitespaces.
-.1   Parentheses for feedback
+Why the apparent difference in command invocation?  Need to test . . .  - TMH
-In the previous section, parantheses were used to group subpatterns together. They can also play another role. When a regular expression successfully matches a string each part of the string that matches a paranthensized subpattern is stored in "expect_out(1,string)" the second in "expect_out(2,string)" etc up to "expect_out(9,string)". The entire pattern matched is stored in "expect_out(0,string)". Everthing before the pattern and the pattern matched is stored in "expect_out(buffer)". The last two assignments work in glob pattern too.
-"a*((ab)*|b)"
-How is this passed to expect_out? It is quite simple. The entire string withing the first parenthesis is stored in 1 (which means up to end of string). The second fount parenthesis is stored in 2. Look for the left parenthesis to determine where the data is put.
-.2   Flags
+Command to break out first ten $PATH environment variable to individual paths each shown on a line of the shell:
--re
--gl
+<pre>
--nocase	Ignore case. Do not use -nocase with uppercase characters in the pattern as it will never match.
+    $ for path in `echo $PATH | cut -d':' -f1-10 --output-delimiter=' '`; do echo $path; done
--notransfer	Prevent expect from removing matching characters from the internal buffer. The characters can be matched repeatedly as long as this option is associated with the pattern. It can be abbreviated with "-n" when expect is running interactively.
+</pre>
--brace	Expect normally see the first argument as a pattern to match, but sometimes you want to give a list of patterns and actions to expect. You can then use -brace to expand the list before it is handled by expect.
-expect -brace { pat1 act1 pat2 act2 }
+-04-23 - Monday, command to obtain summary of directories containing 1GB or more data:
-This can be useful when building up lists of pattern to match with corresponding actions to do.
+<pre>
--i n	Use an alternative spawn_id. This applies to all patterns after the -i flag.
+    $ du -h . | grep [0-9]G
-expect {
+</pre>
- -i $ftp
- "ftp>" "exit"
- eof "exit"
-}
-You can also expect values from multiple spawned processes at the same time. At most one action can be executed just as expect normally do.
+=== <i> [[#top|&uarr;]] [[#references|&darr;]] edit point - shell variable quoting</i> ===
-expect {
-  -i $ftp "ftp> " { ftp_action }
+- 2017-10-19 THU -
- -i $shell $prompt { shell_action }
-}
+Running into issues when need to expand shell variable in single quotes pair . . .
-There is an input buffer associated with each spawn id. So any output from ftp is kept separate from thta of the shell in the example above. When output appear on terminal it will be mixed, unless you expect one at a time or set log_user 0 and then wrote output explictly using send_user $expect_out(buffer). The process that did not match will keep its buffer until matched by next expect command.
-When the expect command match something it record the spawn_id to expect_out(spawn_id) so you can know which process that it matched against.
+[https://unix.stackexchange.com/questions/178411/how-to-use-variables-inside-single-quotes Stack Exchange, Unix forum post 178411]<br />
-You can also set the spawn_id definition to a list of spawn_ids.
+[http://tldp.org/LDP/abs/html/varassignment.html TLPD Advanced Bash Scripting Guide, chapter 4.2 example 4-3 double quotes preserve white space]<br />
-expect {
-  -i "$host1 $host2 $host3" $prompt {
-    an_action $expect_out(spawn_id)
+WIKI WISH LIST - While adding to wiki, Ted noting that would be useful to have relative-depth wiki section markers.  The standard wiki section markers '== ==', '=== ===' and similar have fixed depth.  That is, '== ==' is always a top-level or first-level section in a wiki document, '=== ===' is always a sub-subsection of wiki documents, and '==== ====' a sub-sub-section.  When section gets re-factored into its own article, would be handy to have those section markers rise up to levels of top-most and successive section markers.  - TMH
-  }
-  eof exit
-  -i $host1 another_pattern {host1_action}
-}
+<!-- comment -->
-This example will do an_action if $prompt is matched agains any of the $hostnr, exit if end of file is matched against same list and do host1_action if matchina another_pattern from host1.
-.3   Special patterns
+=== [[#top|&uarr;]] [[#references|&darr;]] example shell script - back up several databases ===
-Note that these patcherns will only match if none of the '-gl', '-re' or '-ex' flags has been used.
-eof	Match when end of file is reached.
-timeout	Match when the timeout value has been reached.
-default	Match when end of file or timeout is reached.
-full_buffer	Match when no other pattern match and expect would otherwise throw away part of the input to make room fore more. When this matches, all of the unmatched input is moved to expect_out(buffer).
-null
-By default null characters are removed from the buffer before expect matching is done. This can be disabled using the remove_nulls command below. If it is disabled null characters will be matched using this special keyword. Null characters can not be matched inside a pattern as expect first look for null characters and then do pattern matching. If a null character is found the characters before it is skilled. These caracters can be found in expect_out(buffer).
-Since the null character is used internally to represent the end of a string unanchored patterns cannot be matched past a null. This is not a problem since null pattern can always be listed last.
-</pre>
+&nbsp;<br />
+Here is a simple shell script to call mysqldump utility and back up several databases.  Couple of things Ted wants to add to this script include script variables to hold back-up filename prefix and infix patterns, and an option to compress the MYSQL dump files . . .
+<i>Figure x - shell script to back-up multiple MYSQL databases</i>
-<!-- comment -->
+<pre>
-=== [[#top|&uarr;]] [[#references|&darr;]] Rust programming language ===
+#!/bin/bash
-There are two editions of the Rust Programming book.  The Rust home page recommends to start by reading the second edition:
-*  https://doc.rust-lang.org/book/second-edition/
-*  https://doc.rust-lang.org/nomicon/
+DATABASE_LIST="information_schema mysql drupal_8p0 phpmyadmin wiki_database"
+user="root"
+pass_phrase_for_mysql="mysql_user_password"
+options_extra="--skip-lock-tables"
+response="n"
-<!-- comment -->
+mode_interactive="n"
-== - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - - ==
-<!-- comment -->
-<!-- SECTION - Aboriginal Linux -->
+echo "shell script starting,"
-== [[#top|&uarr;]] [[#references|&darr;]] Aboriginal Linux - project now defunct, new project is 'makeroot' ==
-Ok, looks like Robert Landley's [https://landley.net/aboriginal/about.html Aboriginal Linux] project has been superceded by [http://landley.net/aboriginal/ mkroot].  Ladnley's newer makeroot project sources are available at GitHub:
+for database in ${DATABASE_LIST};
+do echo "backing up alta-ubuntu database $database . . .";
+#    command="mysqldump --databases $database -u$user -p$pass_phrase_for_mysql $options_extra >> au-database-back-up--${database}.sql"
+    command="mysqldump --databases $database -u$user -p$pass_phrase_for_mysql $options_extra"
+    redirect="au-database-back-up--${database}.sql"
-*  [https://github.com/landley/mkroot makeroot project on GitHub]
+    if [ $mode_interactive = 'y' ]; then
+        echo "build command '$command' and database back-up filename'$redirect',"
+        echo "full command will be '$command' > '$redirect',"
+        echo "trying running this command and redirect? [y/N/q]  yes, no, 'q' to quit"
-Having trouble carrying out the basic build of Aboriginal Linux with armv6l as target . . .
+        read response
+        if [ $response = 'Y' -o $response = 'y' ]; then
+            ${command} > $redirect
+        elif [ $response = 'N' -o $response = 'n' ]; then
+            echo "skipping present command . . ."
+        elif [ $response = 'Q' -o $response = 'q' ]; then
+            echo "stopping script '$0' and exiting."
+            break
+        fi
+        echo
-<pre>
+    else
-   .
+        echo "$0:  backing up database '$database' to file '$redirect' . . ."
-   .
+        ${command} > $redirect
-   .
+        ls -l $redirect
-Confirmed e2fsprogs-1.42.13.tar.gz
+    fi
-Confirmed zlib-1.2.7.tar.bz2
-Confirmed squashfs-4.2.tar.gz
+done
-=== Got all source.
-real    0m2.240s
-user    0m1.188s
-sys     0m0.176s
-=== toybox (host host-tools)
-Snapshot 'toybox'...
-scripts/genconfig.sh
-cc -o kconfig/conf kconfig/conf.c kconfig/zconf.tab.c -DKBUILD_NO_NLS=1 \
-                -DPROJECT_NAME=\"ToyBox\"
-kconfig/conf -D /dev/null Config.in > /dev/null
-scripts/make.sh
-Generate headers from toys/*/*.c...
-generated/newtoys.h Library probe.......
-Make generated/config.h from .config.
-generated/flags.h generated/globals.h generated/help.h
-Compile toybox................................................................................................................................................................generated/obj/nsenter.o: In function `unshare_main':
-nsenter.c:(.text.unshare_main+0x152): undefined reference to `setns'
-collect2: error: ld returned 1 exit status
-make: *** [toybox] Error 1
-Exiting due to errors (host host-tools toybox)
+echo "done."
+exit 0
 </pre>
-*  [http://man7.org/linux/man-pages/man2/setns.2.html Linux kernel routine to setns()]
+=== [[#top|&uarr;]] [[#references|&darr;]] show kernel version script ===
+Following script 'showkversion' can be used in a Linux kernel source tree to determine the kernel's version number, based on the number elements defined in the kernel's top level makefile.
-Robert Landley also has a presence on [https://www.patreon.com/landley www.patreon.com/landley], where he talks about the over-arching goals in his programming and software systems level work.
+<i>Figure x - simple bash script to show kernel version in root of kernel sources tree</i>
+<pre>
+#!/bin/bash
+## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+## Started 2017-12-15 FRI - script to parse and show Linux kernel
+##  version from top-level makefile in set of kernel sources.  Patterns
+##  to `grep` chosen based on kernel version identifiers in first
+##  three lines of typical kernel top-level makefile.  Example:
+##
+##  $ head -n 6 Makefile
+##  VERSION = 4
+##  PATCHLEVEL = 9
+##  SUBLEVEL = 66
+##  EXTRAVERSION =
+##  NAME = Roaring Lionus
+##
+##
+## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-<!-- comment -->
-<!-- SECTION - Linux From Scratch 8.1 - Separate Article -->
+script_name="showkversion"
-== [[#top|&uarr;]] [[#references|&darr;]] Linux From Scratch (Separate Article) ==
-[[LFS-book-8p1-notes|Linux From Scratch Book 8.1 - Build and Notes]]
+if [ ]; then
+    head -n 5 Makefile | grep ^VERSION | cut -d " " -f 3
+    head -n 5 Makefile | grep ^PATCH | cut -d " " -f 3
+    head -n 5 Makefile | grep ^SUBLEVEL | cut -d " " -f 3
+fi
+MAJOR=$(head -n 5 Makefile | grep ^VERSION | cut -d " " -f 3)
+MINOR1=$(head -n 5 Makefile | grep ^PATCH | cut -d " " -f 3)
+MINOR2=$(head -n 5 Makefile | grep ^SUBLEVEL | cut -d " " -f 3)
+KERNEL_REVISION="${MAJOR}.${MINOR1}.${MINOR2}"
+echo
+echo "Kernel version in present kernel sources tree, per makefile, is ${KERNEL_REVISION}"
+echo
+exit 0
+</pre>
@@ Line 709: / Line 921: @@
 <!-- comment -->
-<!-- SECTION - QEMU Emulator -->
+=== [[#top|&uarr;]] [[#references|&darr;]] Other useful shell tutorial references ===
-== [[#top|&uarr;]] [[#references|&darr;]] QEMU Emulator ==
+*  http://tldp.org/LDP/abs/html/textproc.html . . . commands cut, paste, join and others
+*  https://unix.stackexchange.com/questions/131766/why-does-my-shell-script-choke-on-whitespace-or-other-special-characters . . . read shell input line by line
+*  https://stackoverflow.com/questions/7427262/how-to-read-a-file-into-a-variable-in-shell . . . read file into shell variable
-<b>Overview</b>
-Notes on QEMU, an emulator which can help with building and configuring Linux systems to run on embedded computers and development boards.  Ted noting 2017-09-08 that to compile today's latest QEMU source, a 2.10.x release, needed to install Debian stretch packages pkg-config, libglib2.0-dev, dhautoreconf.  Here are some links to downloading QEMU project sources, a manual for using QEMU, and an article about emulating a RaspberryPi system by using QEMU:
+<!-- comment -->
-<b>References:</b>
+== [[#top|&uarr;]] [[#references|&darr;]] Regex tutorials ==
-*  [https://www.qemu.org/download/#source QEMU Emulator, source code download site]
+*  https://www.ntu.edu.sg/home/ehchua/programming/howto/Regexe.html
-*  [https://qemu.weilnetz.de/doc/qemu-doc.html QEMU manual]
-*  [https://en.wikibooks.org/wiki/QEMU/Images How to invoke qemu and give it image to run as operating system]
-QEMU to emulate Arm on Linux . . .
+-11-02 - An interesting blog post and replies, at, I think, Jamie Zawinski's home page.  This one on the use and some limits of regular expressions:
-*  [https://gist.github.com/Liryna/10710751 Emulating ARM on Ubuntu and Debian]
-*  [http://embedonix.com/articles/linux/emulating-raspberry-pi-on-linux/ Emulating Raspberry Pi under Linux, Embedonix article]
-*  [https://medicineyeh.wordpress.com/2016/03/29/buildup-your-arm-image-for-qemu/ Medicineyeh - Build your Arm image for QEMU]
-How to avoid "raw image format" warning . . .
+   *  https://www.jwz.org/blog/2011/11/you-doom-us-all-to-inhuman-toil-for-the-one-whose-name-cannot-be-expressed-in-the-basic-multilingual-plane/
-*  https://unix.stackexchange.com/questions/276480/booting-a-raw-disk-image-in-qemu
+<!-- comment -->
-So got QEMU 2.10.0 sources and dependencies installed, ran `configure` and `make` steps, and let the build process run for an hour or two.  But in the end could not find any `qemu` executable.  Why is the emulator itself apparently missing?  Building latest QEMU under Linux . . .
+== [[#top|&uarr;]] [[#references|&darr;]] `sed` stream editor ==
-*  [https://wiki.qemu.org/Hosts/Linux Building QEMU on Linux type hosts]
+Unix `sed` stream editor, examples and references:
-So I'm following the above article author's typical build steps, and run into this message part-way down those steps, at the step of calling `make`:
+<i>Code snippet - rename multiple files where a substring need be changed:</i>
 <pre>
-user@host-6:~/Downloads/qemu/qemu-2.10.0/bin/debug/native$ make
+   $ for file in `ls ./2109*.*`; do mv $file `ls -1 $file | sed s/2109/2019/` ; done
-Makefile:21: *** This is an out of tree build but your source tree (/home/veris/Downloads/qemu/qemu-2.10.0) seems to have been used for an in-tree build. You can fix this by running "make distclean && rm -rf *-linux-user *-softmmu" in your source tree.  Stop.
-user@host-6:~/Downloads/qemu/qemu-2.10.0/bin/debug/native$
 </pre>
+References on `sed`:
-Ok interesting, I know that QEMU is a complicated project with a complex build process, but clearly I don't know what I'm doing.  Following the above 'distclean' command given in the error message from QEMU's makefile, I'm now able to begin an "out of tree" build as described in the "Building QEMU" article at qemu.org just above.  Tired already however of QEMU project builds taking more than an hour to complete.  Here is one of many articles describing how to invoke `make` to build only limited parts of QEMU project, for example just the pieces needed to emulate ARM type systems:
+*  http://www.grymoire.com/Unix/Sed.html#uh-1
+-08-26:
+*  https://unix.stackexchange.com/questions/375530/use-sed-to-find-and-replace-a-string-in-multiple-files
-*  [https://www.cnx-software.com/2012/03/08/how-to-build-qemu-system-arm-in-linux/ Build qemu-system-arm on Linux host]
+<!-- comment -->
+== [[#top|&uarr;]] [[#references|&darr;]] Other Computer Programming Languages ==
-Ted to test this type of build soon . . .
-On a different note, QEMU build has completed and the stock RaspberryPi Debian "Stretch" image is coming up.  Needed to install a VNC client to interact with the emulated RaspberryPi operating and software, stored in the downloaded .img file from Rpi's web site.  Here's a link to a forum post which clued Ted into Remmina VNC client:
+<!-- comment -->
-*  [https://www.quora.com/How-could-I-connect-to-a-VNC-server-running-on-1-5900 Quora dot com, connect to VNC server]
+=== [[#top|&uarr;]] [[#references|&darr;]] Python Scripting Language ===
+*  https://docs.python.org/2/tutorial/index.html
+*  https://learn.onemonth.com/ruby-vs-python/
-- 2017-11-21 Tuesday -
-The version of qemu which installed from Debian's package list didn't seem to work.  It's been some weeks now since trying that instance, but qemu 2.10.0 works to bring up a command line image built for RaspberryPi.  Here are the versions of the two qemu instances:
-<i>Figure x - locating qemu instances, determining their versions</i>
+<!-- comment -->
+=== [[#top|&uarr;]] [[#references|&darr;]] Expect Utility by Don Libes ===
+Installing 'expect' on Ubuntu 16.04.x LTS host, typical dependencies:
 <pre>
+ted@localhost:~/projects/shell/expect-work$ sudo apt install expect
-user@localhost:~$ which qemu
+Reading package lists... Done
-/usr/bin/qemu
+Building dependency tree
+Reading state information... Done
+The following additional packages will be installed:
+  libfontenc1 libxaw7 libxmu6 libxmuu1 libxtst6 libxv1 libxxf86dga1 tcl-expect tcl8.6 tk8.6 x11-utils xbitmaps xterm
+Suggested packages:
+  tcl-tclreadline mesa-utils xfonts-cyrillic
+The following NEW packages will be installed:
+  expect libfontenc1 libxaw7 libxmu6 libxmuu1 libxtst6 libxv1 libxxf86dga1 tcl-expect tcl8.6 tk8.6 x11-utils xbitmaps xterm
+upgraded, 14 newly installed, 0 to remove and 5 not upgraded.
+Need to get 1,373 kB of archives.
+After this operation, 4,110 kB of additional disk space will be used.
+Do you want to continue? [Y/n] y
+  .
+  .
+  .
+</pre>
-user@localhost:~$ /usr/bin/qemu --version
-QEMU emulator version 1.1.2 (Debian 1.1.2+dfsg-6+deb7u23), Copyright (c) 2003-2008 Fabrice Bellard
-user@localhost:~$ ls /opt/qemu
+Some 'expect' utility references:
-qemu-system-arm
-user@localhost:~$ ls -l /opt/qemu/qemu-system-arm
+*  https://www.unix.com/shell-programming-and-scripting/176054-multiple-while-loops-expect-script.html?s=3aa3009c43b2e834326eea6dfa0d1139
-lrwxrwxrwx 1 root root 83 Sep 12 16:37 /opt/qemu/qemu-system-arm -> /home/user/Downloads/qemu/qemu-2.10.0/bin/debug/native/arm-softmmu/qemu-system-arm
-user@localhost:~$ /opt/qemu/qemu-system-arm --version
+Good short examples covering range of tasks here at Robert Elder blog page, noting md5sum expect script example . . .
-QEMU emulator version 2.10.0
+*  http://blog.robertelder.org/don-libes-expect-unix-automation-tool/
-Copyright (c) 2003-2017 Fabrice Bellard and the QEMU Project developers
-user@localhost:~
+*  https://www.ibm.com/developerworks/community/blogs/brian/entry/when_to_use_expect_scripting_and_when_to_avoid_it10?lang=en Expect script with while-loop
-</pre>
+*  https://wiki.tcl.tk/11584 list of Expect tutorials
+*  https://debaan.blogspot.com/2007/09/simple-expect-ssh-example.html
+*  http://wiki.tcl.tk/11583
-- 2017-11-22 Wednesday -
+How to capture specific results during an expect script's execution:
+*  https://stackoverflow.com/questions/2077721/how-do-you-save-and-parse-a-command-output-in-expect
-Yesterday could not bring up raspbian image in qemu, same image which booted and appeared, and permitted shell based login and shell use a month ago on the local host.  Looking at a new on-line reference for running raspbian images in qemu:
+- 2018-01-30 - Tuesday, picking up from last week researching how to redirect expect output and its spawned processes' output with filtering to log file.  The first reference here at Stackoverflow repeats the useful <code>lindex</code> syntax.  There is also mention of the <code>expect</code> manual and a syntax <code>$::env(action)</code> which can be expressed in an expect script to access an environment variable that is part of the controlling shell . . .
+*  https://stackoverflow.com/questions/11131318/how-to-use-bash-script-variables-in-expect-conditional-statements
-   *  https://ownyourbits.com/2017/02/06/raspbian-on-qemu-with-network-access/
+How to use expect's <code>log_file</code> key word in an expect script:
+*  https://stackoverflow.com/questions/15965504/how-to-create-log-file-for-tcl-script
+From the manual page for expect version 5.45:
-This above article looks really interesting, appears to go to a second installment of the article where the developers there are building some kind of cloud-based or cloud involved web, database, mail and PHP servers.  But on my end having trouble with a kernel panic this morning when invoking qemu-system-arm with a large set of options . . . ok, just located a different invocation of qemu-system-arm version 2.10.0, noting here in following code figure:
+<ul>
+<i>
+<pre>
+       log_file [args] [[-a] file]
+             If a filename is provided, log_file will record a transcript of the session (beginning at that point) in
+             the file.  log_file will stop recording if no argument is given.  Any previous log file is closed.
+             Instead  of  a  filename,  a Tcl file identifier may be provided by using the -open or -leaveopen flags.
+             This is similar to the spawn command.  (See spawn for more info.)
-<i>Figure x - emulate-rpi shell script</i>
+             The -a flag forces output to be logged that was suppressed by the log_user command.
-<pre>
+             By default, the log_file command appends to old files rather than truncating them, for  the  convenience
+             of  being  able  to  turn  logging off and on multiple times in one session.  To truncate files, use the
-#!/bin/bash
+             -noappend flag.
-# Starts raspberry pi image in configuration mode
+             The -info flag causes log_file to return a description of the most recent non-info arguments given.
+</pre>
+</i>
+</ul>
-##----------------------------------------------------------------------
-## - SECTION - script variables
-##----------------------------------------------------------------------
-EMULATOR=/home/veris/Downloads/qemu/qemu-2.10.0/bin/debug/native/arm-softmmu/qemu-system-arm
+Also from the expect manual page, Expect Hints section:
+<ul>
+<i>
+<pre>
+EXPECT HINTS
+       There are a couple of things about Expect that may be non-intuitive.  This section attempts to address some of
+       these things with a couple of suggestions.
+       A common expect problem is how to recognize shell prompts.  Since these are customized differently by  differ-
+       ently  people and different shells, portably automating rlogin can be difficult without knowing the prompt.  A
+       reasonable convention is to have users store a regular expression describing their prompt (in particular,  the
+       end  of it) in the environment variable EXPECT_PROMPT.  Code like the following can be used.  If EXPECT_PROMPT
+       doesn't exist, the code still has a good chance of functioning correctly.
-##----------------------------------------------------------------------
+           set prompt "(%|#|\\$) $"          ;# default prompt
-## - SECTION - original emulator invocation, everything hard-coded
+           catch {set prompt $env(EXPECT_PROMPT)}
-##----------------------------------------------------------------------
-# qemu-system-arm -kernel ./qemu-rpi-kernel/kernel-qemu -cpu arm1176 -m 256 -M versatilepb -no-reboot -serial stdio -append "root=/dev/sda2 panic=1 rootfstype=ext4 rw init=/bin/bash" -hda rpi.img
+           expect -re $prompt
-# qemu-system-arm -kernel ./qemu-rpi-kernel/kernel-qemu -cpu arm1176 -m 256 -M versatilepb -no-reboot -serial stdio -append "root=/dev/sda2 panic=1 rootfstype=ext4 rw" -hda rpi.img
+       I encourage you to write expect patterns that include the end of whatever you expect to see.  This avoids  the
+       possibility  of  answering a question before seeing the entire thing.  In addition . . .
+</pre>
+</i>
+</ul>
+The expect program has some built-in string buffers, and one of these may hold the latest characters received from a spawned process.  Here is a man page excerpt which shows use of one of these expect buffers:
-##----------------------------------------------------------------------
+<ul>
-## - SECTION - invocation, emulator as variable:
+<i>
-##----------------------------------------------------------------------
+<pre>
+       disconnect
+             disconnects a forked process from the terminal.  It continues running in the background.  The process is
+             given its own process group (if possible).  Standard I/O is redirected to /dev/null.
-# ${EMULATOR} -kernel ./qemu-rpi-kernel/kernel-qemu -cpu arm1176 -m 256 -M versatilepb -no-reboot -serial stdio -append "root=/dev/sda2 panic=1 rootfstype=ext4 rw init=/bin/bash" -hda rpi.img
+             The following fragment uses disconnect to continue running the script in the background.
-# Start RaspberryPi in fully functional mode:
+                 if {[fork]!=0} exit
-${EMULATOR} -kernel ./qemu-rpi-kernel/kernel-qemu -cpu arm1176 -m 256 -M versatilepb -no-reboot -serial stdio -append "root=/dev/sda2 panic=1 rootfstype=ext4 rw" -hda rpi.img
+                 disconnect
+                 . . .
+             The following script reads a password, and then runs a program every hour that demands a  password  each
+             time  it is run.  The script supplies the password so that you only have to type it once.  (See the stty
+             command which demonstrates how to turn off password echoing.)
+                 send_user "password?\ "
+                 expect_user -re "(.*)\n"
+                 for {} 1 {} {
+                     if {[fork]!=0} {sleep 3600;continue}
+                     disconnect
+                     spawn priv_prog
+                     expect Password:
+                     send "$expect_out(1,string)\r"
+                     . . .
+                     exit
+                 }
+</pre>
+</i>
+</ul>
+Further looking for expect's built-in string buffers and variables . . .
+*  http://wiki.tcl.tk/17378
-## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+Pattern matching syntax in Don Libe's expect . . .
-## 2017-09-08 FRI - this script copied from http://embedonix.com/articles/linux/emulating-raspberry-pi-on-linux/
-## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-exit 0
+*  http://www.embecosm.com/appnotes/ean8/html/ch03s02s01.html
-</pre>
+*  https://www.pantz.org/software/expect/expect_examples_and_tips.html . . . some timing stuff and <b>expect script blocks</b>
+*  http://www.asic-world.com/scripting/tcl3.html . . . regex in Tcl must enclose pattern in braces.
-The final token <code>rpi.img</code> points to <code>localhost:/home/user/Downloads/raspberrypi/2017-08-16-raspbian-stretch-lite.img</code> which we downloaded from https://www.raspberrypi.org/downloads/raspbian/.  The working qemu invocation doesn't open qemu's native window, but puts to standard out that is the same shell in which qemu invoked, a couple of lines of output from the booting kernel image.  Then using remmina we connect via "VNC server running on ::1:5900".
-In summary shell script in latest figure successfully invokes qemu-system-arm 2.10.0 built from sources about August 2017, and boots up Raspbian Stretch lite image and kernel named kernel-qemu-4.4.34-jessie.  Next figure is screenshot showing successful login, and last login message . . . though emulation was and is very slow on host system!
+From another source, Tcl's string match command:
-<i>Figure x - emulated raspbian stretch lite screenshot, Remmina window</i>
+ if [string match "f*b*" "foobar"] {
+    puts "match"
+ else {
+    puts "no match"
+ }
-[[media:z.png]]
-A shorter script to start raspberrypi kernel plus image, running in QEMU:
+<!-- comment -->
-<pre>
+=== <i>[[#top|&uarr;]] [[#references|&darr;]] edit point - Tool command language Tcl </i> ===
-#!/bin/bash
-qemu-system-arm -kernel ./kernel-qemu-4.4.34-jessie -cpu arm1176 -m 256 -M versatilepb -serial stdio -append "root=/dev/sda2 rootfstype=ext4 rw" -hda ./2017-09-07-raspbian-stretch-lite.img -redir tcp:5022::22 -no-reboot
-exit 0
+<pre>
+"Practical programming
+in Tcl and Tk"
+ISBN 0-13-038560-3
 </pre>
+In using Don Libes' <code>expect</code> utility or program, looks like it will be important and helpful to understand Tool Command Language Tcl to at least some fluency.  Here appears to be a good starting point tutorial for Tcl:
+*  https://www.tutorialspoint.com/tcl-tk/tcl_commands.htm
-- 2017-12-12 WED -
-An excerpt from qemu.org/download#source, on how to download, configure and compile latest QEMU sources:
+Tcl <code>puts</code> built-in command, channels and code to open log file,
+*  https://www.tcl.tk/man/tcl8.4/TclCmd/puts.htm
 <pre>
-"
+Append a log message to a file:
-Build instructions
-To download and build QEMU 2.11.0-rc5:
+set chan [open my.log a]
+set timestamp [clock format [clock seconds]]
+puts $chan "$timestamp - Hello, World!"
+close $chan
+</pre>
-wget https://download.qemu.org/qemu-2.11.0-rc5.tar.xz
-tar xvJf qemu-2.11.0-rc5.tar.xz
-cd qemu-2.11.0-rc5
-./configure
-make
-To download and build QEMU from git:
+Tcl regular expressions:
-git clone git://git.qemu.org/qemu.git
+*  https://www.tcl.tk/man/tcl8.2.3/TclCmd/re_syntax.htm
-cd qemu
-git submodule init
-git submodule update --recursive
-./configure
-make
-The latest development happens on the master branch. The stable trees are located in branches named stable-X.YY branch, where X.YY is the release version.
-"
-</pre>
+Tcl reserved words:
+<pre>
+after		append		array		auto_execok
+auto_import	auto_load	auto_load_index	auto_qualify
+binary		Bgerror		break		catch
+cd		Clock		close		concat
+continue	Dde		default		else
+elseif		Encoding	eof		error
+eval		Exec		exit		expr
+fblocked	Fconfigure	fcopy		file
+fileevent	Flush		for		foreach
+format		Gets		glob		global
+history		If		info		interp
+join		Lappend		lindex		linsert
+list		Llength		load		lrange
+lreplace	Lsearch		lsort		namespace
+open		Package		pid		pkg_mkIndex
+proc		Puts		pwd		read
+regexp		Regsub		rename		resource
+return		Scan		seek		set
+socket		Source		split		string
+subst		Switch		tclLog		tell
+time		Trace		unknown		unset
+update		Uplevel		upvar		variable
+vwait		While
+</pre>
-<!-- comment -->
-<!-- SECTION - Embedded Linux Notes, focus on Rpi Linux Kernel Config -->
-== [[#top|&uarr;]] [[#references|&darr;]] Embedded Linux Notes, focus on Rpi Linux Kernel Config ==
+<!-- comment -->
-Ted looking into a couple of areas of embedded Linux, including [[nn_embedded_linux_notes|custom kernel config for Rpi]], the open source Buildroot project, Tiny-Core Linux and FreeRTOS.  Ted also stashing some links to embedded studies notes on this wiki here:
+=== <i>[[#top|&uarr;]] [[#references|&darr;]] edit point - Tcl pattern matching and anchoring, symbols ^ and $ wrt data not lines</i> ===
-*  [[system_partitions_to_hard_disk|Copying Rpi Linux partitions to hard disk]]
+From the Tcl manual page on-line here is a clue about pattern matching in Tcl scripts, which may explain why we are struggling to obtain matched substrings from sequences of bytes from expect-spawned processes . . .
+<ul>
+<i>
+<pre>
+    Note that in many editors, the ^ and $ match the beginning and end of lines respectively. However, because expect is not line oriented, these characters match the beginning and end of the data (as opposed to lines) currently in the expect matching buffer. (Also, see the note below on "system indigestion.")
+</pre>
+</i>
+</ul>
-<!-- comment -->
+Tcl regular expression syntax:
-== [[#top|&uarr;]] [[#references|&darr;]] FreeRTOS Notes (Separate Article) ==
+*  https://www.tcl.tk/man/tcl8.2.3/TclCmd/re_syntax.htm#M57
-<!-- 2017-12-08 FRI -->
+Expect variables, using global and upvar keywords in Tcl scripts:
-[[FreeRTOS|FreeRTOS notes]]
+*  http://www.huecker.com/msw/tcl/tutorial/Tcl13.shtml
-Ted to move this link to nn wiki article named 'FreeRTOS'.  For now however Ted noting an openssl library named Wolfssl:
-*  https://freertos.org/FreeRTOS-Plus/WolfSSL/WolfSSL.shtml
+Excerpt on Tcl pattern matching from Inguza web site:
-*  https://www.wolfssl.com/
-*  https://www.wolfssl.com/license/
-NOTE 2017-12-10:  this section 'embedded operating systems' to become a shorter list of major significant embedded OS's.  As of 2017 winter Ted studying couple distributions of embedded Linux and FreeRTOS.
-<!-- comment -->
-== [[#top|&uarr;]] [[#references|&darr;]] Bootloader U-Boot ==
-Ted noting after several custom Linux-for-Rpi kernel build attempts that Raspberry Pi board uses a bootloader typically other than GRUB, commonly uses U-boot.  A first tutorial . . . also running into U-boot sources makefile calling a project script which fails to find gcc-6, though /usr/bin/gcc is a symlink to that newer gcc . . .
-*  http://etutorials.org/Linux+systems/embedded+linux+systems/Chapter+9.+Setting+Up+the+Bootloader/9.5+U-Boot/
-*  https://blog.christophersmart.com/2016/10/27/building-and-booting-upstream-linux-and-u-boot-for-raspberry-pi-23-arm-boards/
-After installing manually some twenty or thirty gcc-6-arm-linux and gcc-6, gcc-7 files, and installing more modern version of build-essentials package from Ubuntu release codenamed 'bionic', can now build u-boot.  Tail of messages from build process . . .
-<pre>
-  CC      lib/strto.o
-  CC      lib/strmhz.o
-  LD      lib/built-in.o
-  CC      examples/standalone/stubs.o
-  CC       CC      lib/strto.o
-  CC      lib/strmhz.o
-  LD      lib/built-in.o
-  CC      examples/standalone/stubs.o
-  CC      examples/standalone/hello_world.o
-  LD      examples/standalone/libstubs.o
-  LD      examples/standalone/hello_world
-  OBJCOPY examples/standalone/hello_world.srec
-  OBJCOPY examples/standalone/hello_world.bin
-  LD      u-boot
-  OBJCOPY u-boot.srec
-  OBJCOPY u-boot-nodtb.bin
-  SYM     u-boot.sym
-  COPY    u-boot.bin
-  CFGCHK  u-boot.cfg
-ted@rangari:/var/local/ted/projects/u-boot$ examples/standalone/hello_world.o
-  LD      examples/standalone/libstubs.o
-  LD      examples/standalone/hello_world
-  OBJCOPY examples/standalone/hello_world.srec
-  OBJCOPY examples/standalone/hello_world.bin
-  LD      u-boot
-  OBJCOPY u-boot.srec
-  OBJCOPY u-boot-nodtb.bin
-  SYM     u-boot.sym
-  COPY    u-boot.bin
-  CFGCHK  u-boot.cfg
-ted@rangari:/var/local/ted/projects/u-boot$
-</pre>
-<!-- comment -->
-== [[#top|&uarr;]] [[#references|&darr;]] LPC11U6x Development Board ==
-*  https://community.nxp.com/thread/389139
-*  http://www.embeddedartists.com/products/lpcxpresso/lpclink2.php
-*  https://os.mbed.com/teams/Semtech/code/SX1276TxContinuousWave/
-<!-- comment -->
-==  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - - ==
+<pre>
+   Expect
+The expect suite actually consist just of a few commands: expect, send, spawn and interact and is an extension to TCL.
+Before the expect command can be used a program must be spawned, see expect commands below.
+expect \
+  {match1} {action1} \
+  {match2} {action2} \
+  {match3} {action3} \
+  {match4} {action4}
+It is possible that no such output is encountered within the time period defined by the timeout (variable name "timeout" in seconds, default to 2). In this case expect stops waiting and continues with the next command in the script.
+You can use '*' to match any characters. You can also match using [] syntax and similar.
+expect "\[a-f0-9]"  ; # strongly preferred as \n and similar is not taken as litteral charactesr \ and n.
+expect {a-f0-9}     ; # can also be used
+A note on \ characters. The pattern matcher translate \x to x but this is done once before the pattern matcher. So you need to type \\n to match n. This is especially important for * and ? characters.
+expect "*" ;# match anything (*)
+expect "\n" ;# match linefeed
+expect "\*" ;# match anything
+expect "\\*" ;# match * character
+expect "\\\*" ;# match * character
+expect "\\\\*" ;# match \ followed by anything
+expect "\\\\\*" ;# match \ followed by anything
+expect "\\\\\\*" ;# match \ followed * character
+The [ character is special to both tcl and the pattern matcher so it is especially messy.
+proc xy {} { return "n*w" }
+expect "[xy]" ;# match n followed by anything followed by w
+expect "\[xy]" ;# match x or y
+expect "\\[xy]" ;# match n followed by anything followed by w
+expect "\\\[xy]" ;# match [xy]
+expect "\\\\[xy]" ;# match \ followed by n followed ...
+expect "\\\\\[xy]" ;# match sequence of \ and then x or y.
+The expect command can also take flags. The default flag is -gl for glob pattern matching. It can also take the flag -re for regular expression matching.
+expect {
+  -re "a*" { action_when_a_followed_by_any_a }
+  "b*" { action_when_b_followed_by_anything }
+  -gl "-re" { action_when_real_dash_r_e }
+  eof { action_on_end_of_file }
+  timeout { action_on_command_timeout }
+  default { action_on_command_timeout_or_eof }
+  -re "(abc)*" { action_on_any_number_of_a_b_c }
+  -re "-?(0|\[1-9]\[0-9]*)?\\.?\[0-9]*" { action_on_float_or_integer }
+}
+You can also pass the pattern as a variable.
+set v2pats "pat2 act2"
+set v3pats "pat3 act3"
+expect pat1 act1 $v2pats $v3pats
+Observe that the following expect string is wrong as $v2pats and $v3pats is considered as two different arguments. It will try to match $v2pats as a pattern and $v3pats as an action. Instead build up a string and use the -brace flag. You can not use double quotes for that though, unless you use eval and then the -brace flag is not necessary. You also need to protect the pattern and action inside a [list x] or an extra brace if they contain whitespaces.
+.1   Parentheses for feedback
+In the previous section, parantheses were used to group subpatterns together. They can also play another role. When a regular expression successfully matches a string each part of the string that matches a paranthensized subpattern is stored in "expect_out(1,string)" the second in "expect_out(2,string)" etc up to "expect_out(9,string)". The entire pattern matched is stored in "expect_out(0,string)". Everthing before the pattern and the pattern matched is stored in "expect_out(buffer)". The last two assignments work in glob pattern too.
+"a*((ab)*|b)"
+How is this passed to expect_out? It is quite simple. The entire string withing the first parenthesis is stored in 1 (which means up to end of string). The second fount parenthesis is stored in 2. Look for the left parenthesis to determine where the data is put.
+.2   Flags
+-re
+-gl
+-nocase	Ignore case. Do not use -nocase with uppercase characters in the pattern as it will never match.
+-notransfer	Prevent expect from removing matching characters from the internal buffer. The characters can be matched repeatedly as long as this option is associated with the pattern. It can be abbreviated with "-n" when expect is running interactively.
+-brace	Expect normally see the first argument as a pattern to match, but sometimes you want to give a list of patterns and actions to expect. You can then use -brace to expand the list before it is handled by expect.
+expect -brace { pat1 act1 pat2 act2 }
+This can be useful when building up lists of pattern to match with corresponding actions to do.
+-i n	Use an alternative spawn_id. This applies to all patterns after the -i flag.
+expect {
+ -i $ftp
+ "ftp>" "exit"
+ eof "exit"
+}
+You can also expect values from multiple spawned processes at the same time. At most one action can be executed just as expect normally do.
+expect {
+ -i $ftp "ftp> " { ftp_action }
+ -i $shell $prompt { shell_action }
+}
+There is an input buffer associated with each spawn id. So any output from ftp is kept separate from thta of the shell in the example above. When output appear on terminal it will be mixed, unless you expect one at a time or set log_user 0 and then wrote output explictly using send_user $expect_out(buffer). The process that did not match will keep its buffer until matched by next expect command.
+When the expect command match something it record the spawn_id to expect_out(spawn_id) so you can know which process that it matched against.
+You can also set the spawn_id definition to a list of spawn_ids.
+expect {
+  -i "$host1 $host2 $host3" $prompt {
+    an_action $expect_out(spawn_id)
+  }
+  eof exit
+  -i $host1 another_pattern {host1_action}
+}
+This example will do an_action if $prompt is matched agains any of the $hostnr, exit if end of file is matched against same list and do host1_action if matchina another_pattern from host1.
+.3   Special patterns
+Note that these patcherns will only match if none of the '-gl', '-re' or '-ex' flags has been used.
+eof	Match when end of file is reached.
+timeout	Match when the timeout value has been reached.
+default	Match when end of file or timeout is reached.
+full_buffer	Match when no other pattern match and expect would otherwise throw away part of the input to make room fore more. When this matches, all of the unmatched input is moved to expect_out(buffer).
+null
+By default null characters are removed from the buffer before expect matching is done. This can be disabled using the remove_nulls command below. If it is disabled null characters will be matched using this special keyword. Null characters can not be matched inside a pattern as expect first look for null characters and then do pattern matching. If a null character is found the characters before it is skilled. These caracters can be found in expect_out(buffer).
+Since the null character is used internally to represent the end of a string unanchored patterns cannot be matched past a null. This is not a problem since null pattern can always be listed last.
+</pre>
 <!-- comment -->
-== [[#top|&uarr;]] [[#references|&darr;]] Mobile App Development On Linux ==
+=== [[#top|&uarr;]] [[#references|&darr;]] Rust programming language ===
-*  https://www.raywenderlich.com/122189/introduction-to-open-source-swift-on-linux
+There are two editions of the Rust Programming book.  The Rust home page recommends to start by reading the second edition:
-*  http://www.instructables.com/id/Creating-your-first-iOS-app/
+*  https://doc.rust-lang.org/book/second-edition/
-*  https://developer.apple.com/support/purchase-activation/ . . . required fees to Apple company
-- 2018-10-12 FRI -
+*  https://doc.rust-lang.org/nomicon/
-*  https://developer.apple.com/documentation/corebluetooth
-- 2018-01-15 MON -
-*  https://andrewmichaelsmith.com/2017/02/developing-an-ios-app-on-linux-in-2017/ . . . Developing an iOS app on Linux in 2017
-*  https://itsfoss.com/mount-iphone-ipad-ios-7-ubuntu-13-10/ . . . Ubuntu mount iPhone via libimobiledevice4 libimobiledevice-dev libimobiledevice-util and others
-*  https://beebom.com/how-use-iphone-with-linux/
+=== [[#top|^]] C programming notes ===
+This section really should be in a more prominent space of this wiki.  - TMH
-<!-- comment -->
+This section contains link to Brian Barto post about Untangling Complex C Declarations.  Click here -> [[c_programming_notes|C programming notes]] <- for separate wiki article.
-==  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - - ==
+Typedef and type defining function pointers:
-<i> This section marks a change of topics, from specific technical topics to more world, human and creative area topics. </i>
+<ul>
+*  2019-06-11 https://www.learncpp.com/cpp-tutorial/78-function-pointers/
+</ul>
+CRC types and implementations:
+<ul>
+*  https://stackoverflow.com/questions/10564491/function-to-calculate-a-crc16-checksum
+</ul>
-<!-- comment -->
+Floating point representation and conversions:
-<!-- SECTION - Other Things To Explore -->
+<ul>
+*  http://www.ryanjuckett.com/programming/printing-floating-point-numbers/
-== [[#top|&uarr;]] [[#references|&darr;]] Other Things To Explore ==
+<span id="to_untangle_c_declarations"></span> <span id="untangling_complex_c_delcarations"></span>
+C programmatic reference and dereference rules, dereferencing pointers and pointer expressions:
+*  https://medium.com/@bartobri/untangling-complex-c-declarations-9b6a0cf88c96  <i>"I liked this post about untangling complicated pointer declarations and operators - T.D."</i>
+</ul>
-<br />
-Here are some technical and science topics to explore, perhaps on a rainy day . . .
-Machine learning:
+-11-03
+*  https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.47.1127&rep=rep1&type=pdf
-*  https://github.com/josephmisiti/awesome-machine-learning
+<!-- comment -->
+=== [[#top|^]] C++ references ===
-D Graphics, mathematics behind and programming:
+This section contains beginning level C++ issues and references.  Section here created by need to note some Qt5 related project elements, as Qt is based on C++.  First issue is to understand and document how to implement a QDialog object to act as a sensible dialog box, which can post run-time data to a larger Qt based application.  The first reference below mentions QDialog built-in class functions exec(), accept() and reject(), which appear to be the means to start and show, and to close out a Qt based dialog box . . .
-*  [https://en.wikipedia.org/wiki/Quaternions_and_spatial_rotation Quaternions and Spatial Rotation]
+<ul>
+*  https://stackoverflow.com/questions/12470806/qdialog-exec-and-getting-result-value
+</ul>
+Per help index in QtCreator 3.2.1:
-Creative Commons and other Open Source licensed materials:
+<i>
+<pre>
+void QDialog::accept() [virtual slot]
+Hides the modal dialog and sets the result code to Accepted.
-*  [https://creativecommons.org/website-icons/ Creative Commons licensed icons]
+See also reject() and done().
-*  [https://www.flaticon.com/free-icon/creative-commons-license-symbol_34320 Flaticon.com . . . some freely usable icons, site layout worth review]
+</pre>
+</i>
-Dublin Core:
+The Qt method <code>done()</code> performs more significant work and at least in cases of a dialog being shown with a call to <code>exec()</code> the done() method stops dialog event loop execution:
-*  [http://dublincore.org/documents/2012/06/14/dcmi-terms/?v=elements Dublin Core documents, referenced by Drupal default rss.xml feed page]
+<i>
-*  [https://en.wikipedia.org/wiki/Dublin_Core Dublin Core article on Wikipedia]
+<pre>
-*  [http://www.dublincoregenerator.com/generator.html Dublin Core Generator]
+void QDialog::done(int r) [virtual slot]
+Closes the dialog and sets its result code to r. If this dialog is shown with exec(), done() causes the local event loop to finish, and exec() to return r.
+As with QWidget::close(), done() deletes the dialog if the Qt::WA_DeleteOnClose flag is set. If the dialog is the application's main widget, the application terminates. If the dialog is the last window closed, the QApplication::lastWindowClosed() signal is emitted.
-<!-- comment -->
+See also accept(), reject(), QApplication::activeWindow(), and QApplication::quit().
+</pre>
+</i>
-=== [[#top|&uarr;]] [[#references|&darr;]] <i> edit point </i> ===
-- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;
+So it looks like if we do not call done() then we want to assure that we call exec() only one time during a use session of GWN Unified Tester.  - TMH
-Javascript and JSON:
+<!-- comment -->
+-10-28 Monday:
+G++ error, "template has C linkage":
-*  [https://www.w3schools.com/js/js_json_intro.asp W3C Schools JSON intro]
+*  https://stackoverflow.com/questions/4877705/why-cant-templates-be-within-extern-c-blocks
+-10-30 Wednesday:
+The purposes and use of extern "C" . . .
+<ul>
+*  https://stackoverflow.com/questions/1041866/what-is-the-effect-of-extern-c-in-c
+</ul>
-PC Video, Bochs VBE Extensions:
-*  [http://wiki.osdev.org/Bochs_VBE_Extensions OSDev - Bochs VBE Extensions]
-*  [http://wiki.osdev.org/Main_Page OSDev Dot Org]
+<!-- comment -->
-Perl programming related:
+== - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - - ==
-*  https://perldoc.perl.org/perlpod.html &nbsp; &nbsp; . . . reference to <code>=cut</code> Perl mark-up or directive, plus lots more
-Unix and Linux building blocks:
+<!-- comment -->
-*  [https://en.wikipedia.org/wiki/Name_Service_Switch nss, Name Service Switch]
+<!-- SECTION - Aboriginal Linux -->
-*  "Burrows-Wheeler block sorting text compression algorithm", noted 2017-09-29 FRI from LFS 8.1 chapter 6.21 - TMH
-*  https://www.collabora.com/news-and-blog/blog/2017/03/13/kernel-debugging-with-qemu-overview-tools-available/ . . . kernel debugging and kmemleak
+== [[#top|&uarr;]] [[#references|&darr;]] Aboriginal Linux - project now defunct, new project is 'makeroot' ==
-Webvanta:
-*  [http://www.webvanta.com/services/cloud-cms Webvanta cloud-based Content Management System]
+Ok, looks like Robert Landley's [https://landley.net/aboriginal/about.html Aboriginal Linux] project has been superceded by [http://landley.net/aboriginal/ mkroot].  Ladnley's newer makeroot project sources are available at GitHub:
-Virtual server image creation:
+*  [https://github.com/landley/mkroot makeroot project on GitHub]
-*  [https://research.csc.fi/pouta-adding-images virtual server image creation at cPouta, Finland]
-*  [https://github.com/CSCfi/diskimage-builder-csc-automation disk image builder CSC automation, at Github]
+Having trouble carrying out the basic build of Aboriginal Linux with armv6l as target . . .
-Github Users Sharing Their Work:
+<pre>
-*  [https://github.com/mattions/ Michele Mattioni mattions]
+   .
+   .
+   .
+Confirmed e2fsprogs-1.42.13.tar.gz
+Confirmed zlib-1.2.7.tar.bz2
+Confirmed squashfs-4.2.tar.gz
+=== Got all source.
-<!-- comment -->
+real    0m2.240s
+user    0m1.188s
+sys     0m0.176s
+=== toybox (host host-tools)
+Snapshot 'toybox'...
+scripts/genconfig.sh
+cc -o kconfig/conf kconfig/conf.c kconfig/zconf.tab.c -DKBUILD_NO_NLS=1 \
+                -DPROJECT_NAME=\"ToyBox\"
+kconfig/conf -D /dev/null Config.in > /dev/null
+scripts/make.sh
+Generate headers from toys/*/*.c...
+generated/newtoys.h Library probe.......
+Make generated/config.h from .config.
+generated/flags.h generated/globals.h generated/help.h
+Compile toybox................................................................................................................................................................generated/obj/nsenter.o: In function `unshare_main':
+nsenter.c:(.text.unshare_main+0x152): undefined reference to `setns'
+collect2: error: ld returned 1 exit status
+make: *** [toybox] Error 1
-=== [[#top|&uarr;]] [[#references|&darr;]] <i> edit point </i> ===
+Exiting due to errors (host host-tools toybox)
-- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;
+</pre>
-<!--
-  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -
--->
-Cryptography Scientists and Articles:
+*  [http://man7.org/linux/man-pages/man2/setns.2.html Linux kernel routine to setns()]
-*  [https://www.rambus.com/inventors/inventor-paul-kocher/ Paul Kocher and Rambus]
-*  [https://www.rambus.com/memory-and-interfaces/ Rambus memory and interfaces]
-*  [https://en.wikipedia.org/wiki/Row_hammer side-channel attack known as 'Row hammer', adjacent DRAM cells changed by frequent write operations]
-*  [https://en.wikipedia.org/wiki/Morris_worm Robert Morris internet work 1988]
+Robert Landley also has a presence on [https://www.patreon.com/landley www.patreon.com/landley], where he talks about the over-arching goals in his programming and software systems level work.
-*  [https://en.wikipedia.org/wiki/Simile_(computer_virus) Simile computer virus, metamorphic code]
-*  [https://en.wikipedia.org/wiki/Zmist Zmist metamorphic computer virus]
-<!--
-https://www.convirture.com/company_management.php
-https://www.convirture.com/community.php
-https://www.theregister.co.uk/2012/12/14/convirture_convirt_3_2_vmware_support/
--->
-ARM microcontroller related:
+<!-- comment -->
-*  [http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0337e/Cihcffda.html Nested Vector Interrupt Controller (NVIC)]
+<!-- SECTION - Linux From Scratch 8.1 - Separate Article -->
+== [[#top|&uarr;]] [[#references|&darr;]] Linux From Scratch (Separate Article) ==
-Operating system level programming:
+[[LFS-book-8p1-notes|Linux From Scratch Book 8.1 - Build and Notes]]
-*  [http://www.musl-libc.org/ musl libc home page]
-*  [http://www.etalabs.net/compare_libcs.html musl C library comparison with other C libraries]
-*  [http://www.etalabs.net/overcommit.html memory overcommit]
-Gputils PIC programming tools, W3C Jigsaw validator referenced at end of page
+<!-- comment -->
-*  https://gputils.sourceforge.io/#News
+<!-- SECTION - QEMU Emulator -->
+== [[#top|&uarr;]] [[#references|&darr;]] QEMU Emulator ==
+<b>Overview</b>
-<!-- comment -->
+Notes on QEMU, an emulator which can help with building and configuring Linux systems to run on embedded computers and development boards.  Ted noting 2017-09-08 that to compile today's latest QEMU source, a 2.10.x release, needed to install Debian stretch packages pkg-config, libglib2.0-dev, dhautoreconf.  Here are some links to downloading QEMU project sources, a manual for using QEMU, and an article about emulating a RaspberryPi system by using QEMU:
-<!-- SECTION - Community, Culture, the World -->
-== [[#top|&uarr;]] [[#references|&darr;]] Community, Culture, the World ==
+<b>References:</b>
-*  Morocco weather climate and agriculture . . .
+*  [https://www.qemu.org/download/#source QEMU Emulator, source code download site]
-**  [http://www.our-africa.org/morocco/climate-agriculture Morocco's climate - Our Africa site]
+*  [https://qemu.weilnetz.de/doc/qemu-doc.html QEMU manual]
-**  http://www.essaouira.nu/ecology_climate.htm
+*  [https://en.wikibooks.org/wiki/QEMU/Images How to invoke qemu and give it image to run as operating system]
-**  http://www.worldbank.org/en/news/feature/2015/11/23/green-growth-putting-morocco-in-the-lead-against-climate-change
-*  [https://www.sesptsa.org/featured/2018-tree-recycling/ Southeast Environmental School PTSA]
+QEMU to emulate Arm on Linux . . .
+*  [https://gist.github.com/Liryna/10710751 Emulating ARM on Ubuntu and Debian]
+*  [http://embedonix.com/articles/linux/emulating-raspberry-pi-on-linux/ Emulating Raspberry Pi under Linux, Embedonix article]
+*  [https://medicineyeh.wordpress.com/2016/03/29/buildup-your-arm-image-for-qemu/ Medicineyeh - Build your Arm image for QEMU]
+How to avoid "raw image format" warning . . .
+*  https://unix.stackexchange.com/questions/276480/booting-a-raw-disk-image-in-qemu
-<!-- comment -->
-=== [[#top|&uarr;]] [[#references|&darr;]] Human languages ===
-*  [[nn-english-hindi-glossary|English-Hindi glossary at NN]]
+So got QEMU 2.10.0 sources and dependencies installed, ran `configure` and `make` steps, and let the build process run for an hour or two.  But in the end could not find any `qemu` executable.  Why is the emulator itself apparently missing?  Building latest QEMU under Linux . . .
-*  [https://www.omniglot.com/writing/devanagari_conjuncts.php Devanagari conjunct characters]
+*  [https://wiki.qemu.org/Hosts/Linux Building QEMU on Linux type hosts]
-*  [[cool_new_words|cool new words encountered . . .]]
+So I'm following the above article author's typical build steps, and run into this message part-way down those steps, at the step of calling `make`:
-- 2017-12-15 FRI -
+<pre>
+user@host-6:~/Downloads/qemu/qemu-2.10.0/bin/debug/native$ make
-*  https://etohautakuva.deviantart.com/art/Taugedei-Abugida-Alphasyllabary-Cheatsheet-610277914
+Makefile:21: *** This is an out of tree build but your source tree (/home/veris/Downloads/qemu/qemu-2.10.0) seems to have been used for an in-tree build. You can fix this by running "make distclean && rm -rf *-linux-user *-softmmu" in your source tree.  Stop.
-*  http://langventure.strikingly.com/blog/hindi-abugida-in-action
+user@host-6:~/Downloads/qemu/qemu-2.10.0/bin/debug/native$
-*  https://wsotw.weebly.com/blog/alphabets-abugidas-and-syllabaries
+</pre>
+Ok interesting, I know that QEMU is a complicated project with a complex build process, but clearly I don't know what I'm doing.  Following the above 'distclean' command given in the error message from QEMU's makefile, I'm now able to begin an "out of tree" build as described in the "Building QEMU" article at qemu.org just above.  Tired already however of QEMU project builds taking more than an hour to complete.  Here is one of many articles describing how to invoke `make` to build only limited parts of QEMU project, for example just the pieces needed to emulate ARM type systems:
-<!-- comment -->
-<span id="references"></span>
+*  [https://www.cnx-software.com/2012/03/08/how-to-build-qemu-system-arm-in-linux/ Build qemu-system-arm on Linux host]
-<!-- SECTION - References -->
+Ted to test this type of build soon . . .
-== [[#top|^]] References ==
-<br />
+On a different note, QEMU build has completed and the stock RaspberryPi Debian "Stretch" image is coming up.  Needed to install a VNC client to interact with the emulated RaspberryPi operating and software, stored in the downloaded .img file from Rpi's web site.  Here's a link to a forum post which clued Ted into Remmina VNC client:
-Reproducible builds, byte-wise reproducible software:
-*  http://events.linuxfoundation.org/sites/events/files/slides/reproducible-build-zoo-elc.pdf
-*  https://labs.riseup.net/code/issues/14455
+*  [https://www.quora.com/How-could-I-connect-to-a-VNC-server-running-on-1-5900 Quora dot com, connect to VNC server]
-Server Side services . . .
-<ul>
+- 2017-11-21 Tuesday -
-Apache2 configuration:
-*  https://www.sslshopper.com/apache-redirect-http-to-https.html
+The version of qemu which installed from Debian's package list didn't seem to work.  It's been some weeks now since trying that instance, but qemu 2.10.0 works to bring up a command line image built for RaspberryPi.  Here are the versions of the two qemu instances:
-SSL
-*  [http://server.arcgis.com/en/web-adaptor/latest/install/iis/enable-https-on-your-web-server-server-.htm SSL certificates behind firewall]
+<i>Figure x - locating qemu instances, determining their versions</i>
-DNS
-*  [http://www.tldp.org/HOWTO/DNS-HOWTO.html DNS How-To] at [http://tlpd.org TLDP]
+<pre>
-*  [http://www.tldp.org/HOWTO/DNS-HOWTO.html DNS How-To by Nicolai Langfeldt]
-</ul>
+user@localhost:~$ which qemu
+/usr/bin/qemu
-Coding standards:
+user@localhost:~$ /usr/bin/qemu --version
-*  https://www.kernel.org/doc/html/latest/process/coding-style.html
+QEMU emulator version 1.1.2 (Debian 1.1.2+dfsg-6+deb7u23), Copyright (c) 2003-2008 Fabrice Bellard
+user@localhost:~$ ls /opt/qemu
+qemu-system-arm
+user@localhost:~$ ls -l /opt/qemu/qemu-system-arm
+lrwxrwxrwx 1 root root 83 Sep 12 16:37 /opt/qemu/qemu-system-arm -> /home/user/Downloads/qemu/qemu-2.10.0/bin/debug/native/arm-softmmu/qemu-system-arm
+user@localhost:~$ /opt/qemu/qemu-system-arm --version
+QEMU emulator version 2.10.0
+Copyright (c) 2003-2017 Fabrice Bellard and the QEMU Project developers
+user@localhost:~
+</pre>
+- 2017-11-22 Wednesday -
+Yesterday could not bring up raspbian image in qemu, same image which booted and appeared, and permitted shell based login and shell use a month ago on the local host.  Looking at a new on-line reference for running raspbian images in qemu:
+   *  https://ownyourbits.com/2017/02/06/raspbian-on-qemu-with-network-access/
+This above article looks really interesting, appears to go to a second installment of the article where the developers there are building some kind of cloud-based or cloud involved web, database, mail and PHP servers.  But on my end having trouble with a kernel panic this morning when invoking qemu-system-arm with a large set of options . . . ok, just located a different invocation of qemu-system-arm version 2.10.0, noting here in following code figure:
+<i>Figure x - emulate-rpi shell script</i>
+<pre>
+#!/bin/bash
+# Starts raspberry pi image in configuration mode
+##----------------------------------------------------------------------
+## - SECTION - script variables
+##----------------------------------------------------------------------
+EMULATOR=/home/veris/Downloads/qemu/qemu-2.10.0/bin/debug/native/arm-softmmu/qemu-system-arm
+##----------------------------------------------------------------------
+## - SECTION - original emulator invocation, everything hard-coded
+##----------------------------------------------------------------------
+# qemu-system-arm -kernel ./qemu-rpi-kernel/kernel-qemu -cpu arm1176 -m 256 -M versatilepb -no-reboot -serial stdio -append "root=/dev/sda2 panic=1 rootfstype=ext4 rw init=/bin/bash" -hda rpi.img
+# qemu-system-arm -kernel ./qemu-rpi-kernel/kernel-qemu -cpu arm1176 -m 256 -M versatilepb -no-reboot -serial stdio -append "root=/dev/sda2 panic=1 rootfstype=ext4 rw" -hda rpi.img
+##----------------------------------------------------------------------
+## - SECTION - invocation, emulator as variable:
+##----------------------------------------------------------------------
+# ${EMULATOR} -kernel ./qemu-rpi-kernel/kernel-qemu -cpu arm1176 -m 256 -M versatilepb -no-reboot -serial stdio -append "root=/dev/sda2 panic=1 rootfstype=ext4 rw init=/bin/bash" -hda rpi.img
+# Start RaspberryPi in fully functional mode:
+${EMULATOR} -kernel ./qemu-rpi-kernel/kernel-qemu -cpu arm1176 -m 256 -M versatilepb -no-reboot -serial stdio -append "root=/dev/sda2 panic=1 rootfstype=ext4 rw" -hda rpi.img
+## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+## 2017-09-08 FRI - this script copied from http://embedonix.com/articles/linux/emulating-raspberry-pi-on-linux/
+## - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+exit 0
+</pre>
+The final token <code>rpi.img</code> points to <code>localhost:/home/user/Downloads/raspberrypi/2017-08-16-raspbian-stretch-lite.img</code> which we downloaded from https://www.raspberrypi.org/downloads/raspbian/.  The working qemu invocation doesn't open qemu's native window, but puts to standard out that is the same shell in which qemu invoked, a couple of lines of output from the booting kernel image.  Then using remmina we connect via "VNC server running on ::1:5900".
+In summary shell script in latest figure successfully invokes qemu-system-arm 2.10.0 built from sources about August 2017, and boots up Raspbian Stretch lite image and kernel named kernel-qemu-4.4.34-jessie.  Next figure is screenshot showing successful login, and last login message . . . though emulation was and is very slow on host system!
+<i>Figure x - emulated raspbian stretch lite screenshot, Remmina window</i>
+[[media:z.png]]
+A shorter script to start raspberrypi kernel plus image, running in QEMU:
+<pre>
+#!/bin/bash
+qemu-system-arm -kernel ./kernel-qemu-4.4.34-jessie -cpu arm1176 -m 256 -M versatilepb -serial stdio -append "root=/dev/sda2 rootfstype=ext4 rw" -hda ./2017-09-07-raspbian-stretch-lite.img -redir tcp:5022::22 -no-reboot
+exit 0
+</pre>
+- 2017-12-12 WED -
+An excerpt from qemu.org/download#source, on how to download, configure and compile latest QEMU sources:
+<pre>
+"
+Build instructions
+To download and build QEMU 2.11.0-rc5:
+wget https://download.qemu.org/qemu-2.11.0-rc5.tar.xz
+tar xvJf qemu-2.11.0-rc5.tar.xz
+cd qemu-2.11.0-rc5
+./configure
+make
+To download and build QEMU from git:
+git clone git://git.qemu.org/qemu.git
+cd qemu
+git submodule init
+git submodule update --recursive
+./configure
+make
+The latest development happens on the master branch. The stable trees are located in branches named stable-X.YY branch, where X.YY is the release version.
+"
+</pre>
+<!-- comment -->
+<!-- SECTION - Embedded Linux Notes, focus on Rpi Linux Kernel Config -->
+== [[#top|&uarr;]] [[#references|&darr;]] Embedded Linux Notes, focus on Rpi Linux Kernel Config ==
+-11-09 - Ted to create [[nn_embedded_work|embedded work]] article on this wiki installation, so noting this Friday evening.  - TMH
+Ted looking into a couple of areas of embedded Linux, including [[nn_embedded_linux_notes|custom kernel config for Rpi]], the open source Buildroot project, Tiny-Core Linux and FreeRTOS.  Ted also stashing some links to embedded studies notes on this wiki here:
+*  [[system_partitions_to_hard_disk|Copying Rpi Linux partitions to hard disk]]
+<!-- comment -->
+== [[#top|&uarr;]] [[#references|&darr;]] FreeRTOS Notes (Separate Article) ==
+<!-- 2017-12-08 FRI -->
+[[FreeRTOS|FreeRTOS notes]]
+Ted to move this link to nn wiki article named 'FreeRTOS'.  For now however Ted noting an openssl library named Wolfssl:
+*  https://freertos.org/FreeRTOS-Plus/WolfSSL/WolfSSL.shtml
+*  https://www.wolfssl.com/
+*  https://www.wolfssl.com/license/
+NOTE 2017-12-10:  this section 'embedded operating systems' to become a shorter list of major significant embedded OS's.  As of 2017 winter Ted studying couple distributions of embedded Linux and FreeRTOS.
+<!-- comment -->
+== [[#top|&uarr;]] [[#references|&darr;]] Bootloader U-Boot ==
+Ted noting after several custom Linux-for-Rpi kernel build attempts that Raspberry Pi board uses a bootloader typically other than GRUB, commonly uses U-boot.  A first tutorial . . . also running into U-boot sources makefile calling a project script which fails to find gcc-6, though /usr/bin/gcc is a symlink to that newer gcc . . .
+*  http://etutorials.org/Linux+systems/embedded+linux+systems/Chapter+9.+Setting+Up+the+Bootloader/9.5+U-Boot/
+*  https://blog.christophersmart.com/2016/10/27/building-and-booting-upstream-linux-and-u-boot-for-raspberry-pi-23-arm-boards/
+After installing manually some twenty or thirty gcc-6-arm-linux and gcc-6, gcc-7 files, and installing more modern version of build-essentials package from Ubuntu release codenamed 'bionic', can now build u-boot.  Tail of messages from build process . . .
+<pre>
+  CC      lib/strto.o
+  CC      lib/strmhz.o
+  LD      lib/built-in.o
+  CC      examples/standalone/stubs.o
+  CC       CC      lib/strto.o
+  CC      lib/strmhz.o
+  LD      lib/built-in.o
+  CC      examples/standalone/stubs.o
+  CC      examples/standalone/hello_world.o
+  LD      examples/standalone/libstubs.o
+  LD      examples/standalone/hello_world
+  OBJCOPY examples/standalone/hello_world.srec
+  OBJCOPY examples/standalone/hello_world.bin
+  LD      u-boot
+  OBJCOPY u-boot.srec
+  OBJCOPY u-boot-nodtb.bin
+  SYM     u-boot.sym
+  COPY    u-boot.bin
+  CFGCHK  u-boot.cfg
+ted@rangari:/var/local/ted/projects/u-boot$ examples/standalone/hello_world.o
+  LD      examples/standalone/libstubs.o
+  LD      examples/standalone/hello_world
+  OBJCOPY examples/standalone/hello_world.srec
+  OBJCOPY examples/standalone/hello_world.bin
+  LD      u-boot
+  OBJCOPY u-boot.srec
+  OBJCOPY u-boot-nodtb.bin
+  SYM     u-boot.sym
+  COPY    u-boot.bin
+  CFGCHK  u-boot.cfg
+ted@rangari:/var/local/ted/projects/u-boot$
+</pre>
+<!-- comment -->
+== [[#top|&uarr;]] [[#references|&darr;]] LPC11U6x Development Board ==
+*  https://community.nxp.com/thread/389139
+*  http://www.embeddedartists.com/products/lpcxpresso/lpclink2.php
+*  https://os.mbed.com/teams/Semtech/code/SX1276TxContinuousWave/
+<!-- comment -->
+== [[#top|&uarr;]] [[#references|&darr;]] avr-libc ==
+<pre>
+./avr-libc-1.8.0/include/avr/iom8.h:634:#if !defined(__AVR_LIBC_DEPRECATED_ENABLE__)
+./avr-libc-1.8.0/include/avr/iom8.h:657:#endif  /* !defined(__AVR_LIBC_DEPRECATED_ENABLE__) */
+ .
+ .
+ .
+/* Deprecated items */
+#if !defined(__AVR_LIBC_DEPRECATED_ENABLE__)
+#pragma GCC system_header
+#pragma GCC poison SIG_INTERRUPT0
+#pragma GCC poison SIG_INTERRUPT1
+#pragma GCC poison SIG_OUTPUT_COMPARE2
+#pragma GCC poison SIG_OVERFLOW2
+#pragma GCC poison SIG_INPUT_CAPTURE1
+#pragma GCC poison SIG_OUTPUT_COMPARE1A
+#pragma GCC poison SIG_OUTPUT_COMPARE1B
+#pragma GCC poison SIG_OVERFLOW1
+#pragma GCC poison SIG_OVERFLOW0
+#pragma GCC poison SIG_SPI
+#pragma GCC poison SIG_UART_RECV
+#pragma GCC poison SIG_UART_DATA
+#pragma GCC poison SIG_UART_TRANS
+#pragma GCC poison SIG_ADC
+#pragma GCC poison SIG_EEPROM_READY
+#pragma GCC poison SIG_COMPARATOR
+#pragma GCC poison SIG_2WIRE_SERIAL
+#pragma GCC poison SIG_SPM_READY
+#endif  /* !defined(__AVR_LIBC_DEPRECATED_ENABLE__) */
+</pre>
+<!-- comment -->
+== [[#top|&uarr;]] [[#references|&darr;]] EWAVR, IAR Workbench, Keil compiler notes ==
+-01-03 THU
+*  http://www.keil.com/support/man/docs/c51/c51_le_sfr.htm
+<!-- comment -->
+==  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - - ==
+== [[#top|&uarr;]] [[#references|&darr;]] Yocto References ==
+*  [https://github.com/toradex/meta-product Yocto meta-product project by Toradex]
+<!-- comment -->
+==  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - - ==
+<!-- comment -->
+== [[#top|&uarr;]] [[#references|&darr;]] Mobile App Development On Linux ==
+*  https://www.raywenderlich.com/122189/introduction-to-open-source-swift-on-linux
+*  http://www.instructables.com/id/Creating-your-first-iOS-app/
+*  https://developer.apple.com/support/purchase-activation/ . . . required fees to Apple company
+- 2018-10-12 FRI -
+*  https://developer.apple.com/documentation/corebluetooth
+- 2018-01-15 MON -
+*  https://andrewmichaelsmith.com/2017/02/developing-an-ios-app-on-linux-in-2017/ . . . Developing an iOS app on Linux in 2017
+*  https://itsfoss.com/mount-iphone-ipad-ios-7-ubuntu-13-10/ . . . Ubuntu mount iPhone via libimobiledevice4 libimobiledevice-dev libimobiledevice-util and others
+*  https://beebom.com/how-use-iphone-with-linux/
+=== [[#top|&uarr;]] [[#references|&darr;]] Android programming ===
+*  https://www.ntu.edu.sg/home/ehchua/programming/android/Android_3D.html
+<!-- comment -->
+==  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - - ==
+<!-- comment -->
+== [[#top|&uarr;]] [[#references|&darr;]] Toradex embedded ARM computers ==
+Search for Toradex asymmetric core 'system on a module' board:
+*  [https://docs.toradex.com/104446-colibri-arm-som-imx6ull-datasheet.pdf 104446-colibri-arm-som-imx6ull-datasheet.pdf] . . . looks like this may be only single core, not dual heterogeneous core
+It looks like Colibri iMX7S and iMX7D are two-core and three-core processor based modules, with asymmetric cores to handle different kinds of data processing more efficiently,
+*  Toradex PN: 00391100 - Colibri iMX7 Dual 1GB | V1.1A
+*  Toradex PN: 01351101 - Iris carrier board
+Looks like the Iris carrier board is a smaller form, less featured but more economical carrier board to support use of iMX7D/S systems on modules:
+*  https://developer.toradex.com/products/iris-carrier-board
+Software to install on this module:
+*  https://www.toradex.com/computer-on-modules/colibri-arm-family/nxp-freescale-imx7
+Software projects and stacks to run on asymmetric core systems:
+*  https://community.nxp.com/docs/DOC-104422
+<!-- comment -->
+=== [[#top|&uarr;]] [[#references|&darr;]] Build U-boot and Linux kernel from source ===
+*  https://developer.toradex.com/knowledge-base/build-u-boot-and-linux-kernel-from-source-code
+<!-- comment -->
+<!-- SECTION - Arduino Development Kit and Documentation -->
+=== [[#top|&uarr;]] [[#references|&darr;]] Arduino Development Kit and Documentation ===
+Looking into Arduino boards as a means to configure an I2C protocol programmer . . .
+Arduino Uno development board datasheet:
+*  https://www.farnell.com/datasheets/1682209.pdf
+Arduino IDE software download:
+*  https://www.arduino.cc/en/Main/Software
+Getting started:
+*  https://www.arduino.cc/en/Guide/HomePage
+**  https://www.arduino.cc/en/Guide/Linux
+A more specifically purposed interface and or programming board called 'Aardvark' . . .
+*  https://www.totalphase.com/support/articles/200468316
+FreeRTOS on Arduino development boards . . .
+*  https://github.com/feilipu/Arduino_FreeRTOS_Library
+<!-- comment -->
+==  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - - ==
+<!-- comment -->
+== [[#top|&uarr;]] [[#references|&darr;]] Electronics ==
+*  https://www.sparkfun.com/products/18572
+Transistor, FETs, Op-amps . . .
+<ul>
+  <li> https://www.electronics-tutorials.ws/amplifier/transistor-biasing.html <br />
+  <li> http://bg-electronics.de/shop/product_info.php/products_id/6409/language/en   . . . MPSA14 Darlington pair NPN transistor <br />
+</ul>
+Photovoltaics . . .
+<ul>
+  <li> https://www.digikey.com/en/articles/techzone/2018/sep/overcoming-power-system-design-challenges-in-1500-vdc-photovoltaic-systems?utm_medium=email&utm_source=tnl&utm_campaign=40284_TNL1811A&utm_content=article1learnmore_US&utm_cid=9726770&mkt_tok=eyJpIjoiWkRFeE1qQmxOMlF4T1dFeCIsInQiOiJLbDVRQkhIUmpGMThyK054VWhLZGFxWmJ5OUpyMHMrdGVKZVdxWnluM1wvRVgxdWcyTzNWQnJrd0wzTlk1SXpqZHZvMWxDNGd4blB3bGFWdWFOSWVsMTNmbWswU1M5aVZhck8wTm1ZK3FBZzFUQXJkK2NZdXlzZng1S2lqTGpob1UifQ%3D%3D <br />
+</ul>
+Analog computers
+<ul>
+  <li>  http://www.analogmuseum.org/library/handbook_of_analog_computation.pdf
+</ul>
+<!-- comment -->
+=== [[#top|&uarr;]] [[#references|&darr;]] tools and hardware ===
+<ul>
+*  https://www.amazon.com/Illuminated-Jewelers-Trichome-Formline-Supply/dp/B073HWZGP3/ref=sr_1_40?hvadid=241934704451&hvdev=c&hvlocphy=9033803&hvnetw=g&hvpos=1t1&hvqmt=e&hvrand=14352835026335723525
+</ul>
+<ul>
+-razradnii kontrolerya . . .
+*  https://docplayer.ru/amp/27429677-32-razryadnyy-kontroller-dlya-aviacionnogo-primeneniya-1986ve1t-k1986ve1t-mdr32f1qi-k1986ve1n4.html
+</ul>
+=== [[#top|&uarr;]] [[#references|&darr;]] measurement equipment ===
+-10-27
+<ul>
+https://saving.em.keysight.com/en/used/oscilloscopes-digital-waveform-analyzers
+</ul>
+Not used but I have this 4 channel 100mhz scope that i like a lot. $500 with built-in i2c/spi/uart/canbus decoding
+https://siglentna.com/product/sds1104x-e-100-mhz/
+https://www.youtube.com/watch?v=Kay4Jk2DHuE
+https://www.youtube.com/watch?v=Cwbwq-AKbPc
+SiglentSiglent
+SDS1104X-E (100 MHz) | Siglent
+Bandwidth: 100 MHz Channels: 4 Real time sampling rate: 1 GSa/s (Total of 2 A-to-D converters) Maximum capture rate: (100,000 in Normal mode, 400,000 in Sequence mode) Memory depth: 14 Mpts Bode Plot function (Requires SIGLENT SDG X or SAG1021 function generator) Search / Navigate functions Web-Based browser remote control Optional Wi-Fi dongle Optional MSO capability
+YouTubeYouTube | EEVblog
+EEVblog #1042 - Siglent's $499 SDS1104X-E 4CH Oscilloscope Teardown
+<!-- comment -->
+=== [[#top|&uarr;]] [[#references|&darr;]] Modbus protocol ===
+<ul>
+[[modbus_notes|Modbus protocol notes]]
+</ul>
+<!-- SECTION - Other Things To Explore -->
+== [[#top|&uarr;]] [[#references|&darr;]] <!-- [[#top|^]] --> Mathematica ==
+Mathematical symbols:
+*  https://en.wikipedia.org/wiki/Glossary_of_mathematical_symbols
+*  https://en.wikipedia.org/wiki/List_of_mathematical_symbols_by_subject
+Important mathematical topics:
+*  https://en.wikipedia.org/wiki/Pure_mathematics
+*  ( applied mathematics link to go here )
+<!-- comment -->
+=== [[#top|^]] Books on mathematics ===
+Books on mathematics to explore:
+<ul>
+*  "Lectures and Problems: A Gift to Young Mathematicians (MSRI Mathematical Circles Library)
+by V. I. Arnold (Author)"
+On-line lecture notes:
+*  https://tutorial.math.lamar.edu/classes/calci/IndefiniteIntegrals.aspx   Paul's On-line Notes
+*  An excellent book on the FFT is: E. Oran Brigham, The Fast Fourier Transform, PrenticeHall, Englewood Cliffs, NJ, 1974.
+</ul>
+CRC, RSA and other mathematical areas . . .
+<ul>
+*  https://en.wikipedia.org/wiki/Cyclic_redundancy_check
+*  [https://en.wikipedia.org/wiki/TWINKLE Integer factorization device TWINKLE by Adi Shamir, of RSA developer trio]
+*  [https://en.wikipedia.org/wiki/TWIRL TWIRL factorization device, short article at Wikipedia]
+*  [https://en.wikipedia.org/wiki/General_number_field_sieve General Number Field Sieve]
+*  [https://en.wikipedia.org/wiki/Heuristic Heuristic way explained]
+*  [https://en.wikipedia.org/wiki/L-notation L-notation, to express computational complexity of algorithms]
+*  [https://en.wikipedia.org/wiki/Discrete_logarithm discrete logarithms]
+</ul>
+Applied math . . .
+<ul>
+*  https://owlcation.com/stem/Everything-About-Triangles-and-More-Isosceles-Equilateral-Scalene-Pythagoras-Sine-and-Cosine
+</ul>
+Fractal geometry and math . . .
+<ul>
+*  http://mathworld.wolfram.com/StrangeAttractor.html
+*  http://mathworld.wolfram.com/LorenzAttractor.html
+</ul>
+Quantum computing and Shor's algorithm . . .
+<ul>
+*  https://en.wikipedia.org/wiki/Shor%27s_algorithm   algoritmo de Shor
+*  https://en.wikipedia.org/wiki/Lenstra_elliptic-curve_factorization#Quantum_version_(GEECM) GEECM
+</ul>
+---
+<ul>
+*  https://en.wikipedia.org/wiki/Condensed_matter_physics
+*  https://en.wikipedia.org/wiki/Bose%E2%80%93Einstein_condensate
+</ul>
+---
+<ul>
+*  https://www.cnet.com/pictures/take-a-look-at-googles-quantum-computing-technology/17/
+</ul>
+<!-- comment -->
+=== [[#top|^]] Fast Fourier Transform FFT ===
+*  https://en.wikipedia.org/wiki/Fast_Fourier_transform
+<ul>
+*  https://en.wikipedia.org/wiki/Big_O_notation
+*  https://en.wikipedia.org/wiki/Root_of_unity
+Other FFT algorithms:
+*  https://en.wikipedia.org/wiki/Hexagonal_fast_Fourier_transform
+</ul>
+*  https://mathworld.wolfram.com/FastFourierTransform.html  Wolfram Math World, Fast Fourier Transform
+<!-- comment -->
+Other mathematical topics:
+<ul>
+*  https://en.wikipedia.org/wiki/Field_(mathematics)
+*  https://en.wikipedia.org/wiki/Riemann_zeta_function
+</ul>
+<!-- comment -->
+== [[#top|&uarr;]] [[#references|&darr;]] <!-- [[#top|^]] --> Literature ==
+Liturature and Authors of the World . . .
+<ul>
+*  https://www.literarytraveler.com/articles/tolkien_lewis_england/
+</ul>
+<!-- comment -->
+== [[#top|&uarr;]] [[#references|&darr;]] Other Things To Explore ==
+Human health:
+*  https://getpocket.com/explore/item/a-mental-disease-by-any-other-name-2094105417
+<br />
+Here are some technical and science topics to explore, perhaps on a rainy day . . .
+Machine learning:
+*  https://github.com/josephmisiti/awesome-machine-learning
+Containers and DevOps:
+*  https://developers.redhat.com/products/rhoar/download/?sc_cid=701f2000000tvScAAI&gclid=CjwKCAiA0O7fBRASEiwAYI9QAqRy2uRVKve05ZeAn8HVRcjtfdmXR73RIgBWVcAylg-TzCoszXBrkRoC9j8QAvD_BwE&gclsrc=aw.ds
+*  https://www.sumologic.com/blog/devops/how-containerization-enables-devops/
+*  https://cloud.google.com/kubernetes-engine/
+*  https://clouddocs.f5.com/products/connectors/k8s-bigip-ctlr/v1.7/
+*  https://kubernetes.io/docs/concepts/services-networking/ingress/
+*  https://kubernetes.io/docs/tasks/run-application/run-stateless-application-deployment/
+D Graphics, mathematics behind and programming:
+<ul>
+*  [https://en.wikipedia.org/wiki/Quaternions_and_spatial_rotation Quaternions and Spatial Rotation]
+- 2018-06-21 Thursday -
+*  https://en.wikipedia.org/wiki/OpenMW
+*  https://en.wikipedia.org/wiki/Bullet_(software)
+</ul>
+Creative Commons and other Open Source licensed materials:
+*  [https://creativecommons.org/website-icons/ Creative Commons licensed icons]
+*  [https://www.flaticon.com/free-icon/creative-commons-license-symbol_34320 Flaticon.com . . . some freely usable icons, site layout worth review]
+Dublin Core:
+<ul>
+*  [http://dublincore.org/documents/2012/06/14/dcmi-terms/?v=elements Dublin Core documents, referenced by Drupal default rss.xml feed page]
+*  [https://en.wikipedia.org/wiki/Dublin_Core Dublin Core article on Wikipedia]
+*  [http://www.dublincoregenerator.com/generator.html Dublin Core Generator]
+</ul>
+Zdyes mnogo informatsia:  <!-- 20109-08-09 -->
+<ul>
+*  https://ertelecom.ru/t/ru/
+</ul>
+<!-- comment -->
+=== [[#top|^]] DYI laptop by Olimex ===
+*  https://www.olimex.com/Products/DIY-Laptop/
+<!-- comment -->
+=== [[#top|&uarr;]] [[#references|&darr;]] <i> edit point </i> ===
+- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;
+Javascript and JSON:
+*  [https://www.w3schools.com/js/js_json_intro.asp W3C Schools JSON intro]
+PC Video, Bochs VBE Extensions:
+*  [http://wiki.osdev.org/Bochs_VBE_Extensions OSDev - Bochs VBE Extensions]
+*  [http://wiki.osdev.org/Main_Page OSDev Dot Org]
+Perl programming related:
+*  https://perldoc.perl.org/perlpod.html &nbsp; &nbsp; . . . reference to <code>=cut</code> Perl mark-up or directive, plus lots more
+Unix and Linux tools, software and building blocks:
+*  [https://en.wikipedia.org/wiki/Name_Service_Switch nss, Name Service Switch]
+*  "Burrows-Wheeler block sorting text compression algorithm", noted 2017-09-29 FRI from LFS 8.1 chapter 6.21 - TMH
+*  https://www.collabora.com/news-and-blog/blog/2017/03/13/kernel-debugging-with-qemu-overview-tools-available/ . . . kernel debugging and kmemleak
+*  https://manned.org/obex-data-server/1d713e98   . . . obex data server
+GNU Make book on-line . . .
+*  http://mitechie.com/
+Webvanta:
+*  [http://www.webvanta.com/services/cloud-cms Webvanta cloud-based Content Management System]
+Virtual server image creation:
+*  [https://research.csc.fi/pouta-adding-images virtual server image creation at cPouta, Finland]
+*  [https://github.com/CSCfi/diskimage-builder-csc-automation disk image builder CSC automation, at Github]
+Github Users Sharing Their Work:
+*  [https://github.com/mattions/ Michele Mattioni mattions]
+<!-- comment -->
+=== [[#top|&uarr;]] [[#references|&darr;]] <i> edit point </i> ===
+- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;- - - - - &nbsp;
+<!--
+  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -  - - - - -
+-->
+Cryptography Scientists and Articles:
+*  [https://www.rambus.com/inventors/inventor-paul-kocher/ Paul Kocher and Rambus]
+*  [https://www.rambus.com/memory-and-interfaces/ Rambus memory and interfaces]
+*  [https://en.wikipedia.org/wiki/Row_hammer side-channel attack known as 'Row hammer', adjacent DRAM cells changed by frequent write operations]
+*  [https://en.wikipedia.org/wiki/Morris_worm Robert Morris internet work 1988]
+*  [https://en.wikipedia.org/wiki/Simile_(computer_virus) Simile computer virus, metamorphic code]
+*  [https://en.wikipedia.org/wiki/Zmist Zmist metamorphic computer virus]
+<!--
+https://www.convirture.com/company_management.php
+https://www.convirture.com/community.php
+https://www.theregister.co.uk/2012/12/14/convirture_convirt_3_2_vmware_support/
+-->
+ARM microcontroller related:
+*  [http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0337e/Cihcffda.html Nested Vector Interrupt Controller (NVIC)]
+Operating system level programming:
+*  [http://www.musl-libc.org/ musl libc home page]
+*  [http://www.etalabs.net/compare_libcs.html musl C library comparison with other C libraries]
+*  [http://www.etalabs.net/overcommit.html memory overcommit]
+Gputils PIC programming tools, W3C Jigsaw validator referenced at end of page
+*  https://gputils.sourceforge.io/#News
+<!-- comment -->
+<span id="musica y liricos"></span>
+<!-- SECTION - music and lyrics -->
+=== [[#top|&uarr;]] [[#references|&darr;]] music and lyrics ===
+*  https://www.youtube.com/watch?v=Nmqitm6cfuU   . . . I am Omni - Back At It - featuring Myka 9
+*  http://ohhla.com/anonymous/blackstr/rm_bside/little_b.blk.txt
+<ul>
+*  https://www.youtube.com/watch?v=RTREDvH8H4g
+</ul>
+---
+*  https://www.youtube.com/watch?v=4SpWuseQGys   Jew harp, Ted talk and Vilnius
+https://www.wish.com/product/59b6c3c68f545e607c2adf30?hide_login_modal=true&from_ad=goog_shopping&_display_country_code=US&_force_currency_code=USD&pid=googleadwords_int&c=%7BcampaignId%7D&ad_cid=59b6c3c68f545e607c2adf30&ad_cc=US&ad_curr=USD&ad_price=48.00&campaign_id=7203534630&gclid=EAIaIQobChMIoZKHvqS06AIVEh-tBh2I6wv-EAQYASABEgKuAvD_BwE&share=web
+<!-- comment -->
+<span id="plant_resources"></span>
+<!-- SECTION - Plant resources -->
+=== [[#top|&uarr;]] [[#references|&darr;]] plant and animal references ===
+Searching Google and Amazon for bottom heat sources for seed germination:
+"
+Seedfactor
+MET certified Seedling Heat Mat, Seedfactor Waterproof Durable Germination Station Heat Mat, Warm Hydroponic Heating Pad for Indoor Home Gardening Seed Starter(10" x 20")
+"
+*  [https://davesgarden.com/guides/articles/view/556 Heating mats article by Jill M. Nicolaus]
+*  https://en.wikipedia.org/wiki/Osmia_bicolor
+*  https://nativebeeology.com/mind-your-bees-and-gardens-2/carpenter-bee/ bufflehead mason bee
+Aloe references . . .
+<ul>
+Aloe maculata, bontalwyne:
+<ul>
+*  http://clarensnews.co.za/aloe-maculata-common-soap-aloe-bontalwyne/
+*  http://pza.sanbi.org/aloe-maculata
+*  https://www.researchgate.net/publication/283348154_Review_of_Aloe_Species%27_Medicinal_Properties_and_Bioactive_Compounds
+</ul>
+[[file:FOPB4-51.pdf|FOBP284 Rodriguez aloe studies paper]]
+</ul>
+-04-10
+Cork trees . . .
+<ul>
+*  http://www.corkforest.org/harvesting-the-cork-oak/
+</ul>
+Invasive plants . . .
+<ul>
+*  https://www.nybg.org/blogs/plant-talk/tag/amur-cork-tree/
+</ul>
+==== [[#top|^]] Cacti ====
+<ul>
+*  https://www.greenfoxlandscapesupply.com/fishhook-barrel-cactus Fishhook barrel cactus
+*  https://cals.arizona.edu/pima/gardening/aridplants/Ferocactus_wislizenii.html "Page not found" but mentions <i>ferocactus wislizenii</i>
+*  http://txmg.wpengine.netdna-cdn.com/williamson/files/Cold-Hardy-Cacti-Succulents-03-11.pdf cold hardiness of cacti, list of many
+*  http://www.phoenixdesertnursery.com/articles.php?article=5 Phoenix Desert Nursery, cactus article mentions claret cup and many others, cold hardiness
+*  http://www.[[#top|^]] americansouthwest.net/plants/cacti/ferocactus-wislizeni.html
+*  http://www.llifle.com/Encyclopedia/CACTI/Family/Cactaceae/4317/Ferocactus_macrodiscus
+*  http://www.llifle.com/plant_album/4317/
+*  https://en.wikipedia.org/wiki/Echinocereus_rigidissimus
+*  https://www.pinterest.co.uk/pin/716846465660891130/
+*  http://www.cactusinhabitat.org/index.php?p=specie&id=46&l=en
+- 2018-08-24 - Friday, search for cold hardiness of echinopsis oxygona:
+*  https://worldofsucculents.com/echinopsis-oxygona-easter-lily-cactus
+- 2019-07-19 - Friday, Frailea cactus native to Brazil
+*  https://en.wikipedia.org/wiki/Frailea
+</ul>
+<!-- comment -->
+==== [[#top|^]] Agavacae ====
+<ul>
+*  https://jcra.ncsu.edu/horticulture/plant-profiles/details.php?ID=98
+</ul>
+<!-- comment -->
+==== [[#top|^]] Nursurias ====
+<ul>
+*  https://www.highcountrygardens.com/perennial-plants/agave/agave-utahensis-ssp-kaibabensis
+<ul>
+Excerpt from this page:
+<i>
+"Planting Instructions
+. Cacti, agaves, and tap-rooted succulents (Aloinopsis, Titanopsis, Nananthus) should be transplanted bare-root. Let the soil in the pot dry out for a few days. Then remove the pot and gently loosen the soil so it falls away from the roots. Trim off any broken roots. Bare root plants should then be planted into a shallow hole. Spread out the roots evenly and sprinkle the soil into the hole until full. The base of the plant should rest on top of the soil. Mulch with a 1⁄2”-1” thick layer of pea-sized gravel around the base of the plant to protect it from contact with soggy soil over the winter months. (See planting diagram on page 12 of our Planting Guide.)
+</i>
+</ul>
+TERMINOLOGY:  https://en.wikipedia.org/wiki/Cleistogamy
+</ul>
+<!-- comment -->
+- 2018-08-06 Monday -
+<ul>
+*  https://www.journals.uchicago.edu/doi/pdfplus/10.1086/277683   . . . lithurge, cactus bees
+</ul>
+Wildflowers . . .
+<ul>
+*  http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=p840   . . . lychnis coronaria, <i>rose campion</i> native to Europe
+*  https://en.wikipedia.org/wiki/Silene_coronaria
+</ul>
+Iris and Bulbs . . .
+<ul>
+*  http://www.srgc.net/forum/index.php?topic=9952.210   . . . Scottish Rock Garden Club, Pat Toolen seedling PT0343
+</ul>
+<ul>
+*  https://butterfly-conservation.org/moths/identify-a-moth
+</ul>
+<!-- comment -->
+Personal project notes . . .
+<ul>
+*  [[bookmarked_paths|bookmarked paths]] of various projects
+</ul>
+-10-21
+*  https://www.indefenseofplants.com/blog/2015/7/23/an-orchid-invader-with-an-interesting-ecology   helleborine orchid
+<!-- comment -->
+==== [[#top|^]] plant pathology ====
+https://www.apsnet.org/publications/phytopathology/backissues/Documents/1971Articles/Phyto61n08_926.PDF
+<!-- comment -->
+<!-- SECTION - Food and Cooking -->
+== [[#top|^]] Technology History and Evolution ==
+Moore's Law and CMOS scaling ways:
+*  https://meroli.web.cern.ch/lecture_scaled_CMOS_Technology.html
+*  https://en.wikipedia.org/wiki/65_nm_process
+*  https://en.wikipedia.org/wiki/Low-%CE%BA_dielectric
+<!-- comment -->
+== [[#top|^]] Astronomy ==
+Physics topics relating to astronomy:
+<ul>
+*  https://en.wikipedia.org/wiki/Speed_of_light
+*  https://en.wikipedia.org/wiki/Parsec
+</ul>
+Black holes and some of their key features as we know them so far:
+<ul>
+*  https://en.wikipedia.org/wiki/Event_Horizon_Telescope
+*  https://en.wikipedia.org/wiki/Kerr_metric Kerr metric as applies to black holes
+-01-30
+*  https://www.shelyak.com/how-to-measure-the-redshift-of-a-galaxy/?lang=en
+</ul>
+Black holes and General Relativity . . .
+<ul>
+*  https://en.wikipedia.org/wiki/Chandrasekhar_limit   Chandrasekhar Limit of mass of stars and specifically white dwarf stars
+</ul>
+<!-- comment -->
+== [[#top|^]] Food and Cooking ==
+*  https://getpocket.com/explore/item/the-best-ever-eggplant-parmigiana?utm_source=pocket-newtab  Italian eggplant parmigiana
+Turkish traditional dishes, borek . . .
+<ul>
+*  https://www.seriouseats.com/2012/02/how-to-make-turkish-burek.html
+</ul>
+Search also for simit, imam bayidi, kafta kabab
+<!-- comment -->
+<span id="references"></span>
+<!-- SECTION - References -->
+== [[#top|^]] References ==
+[[Notes|Neela Nurseries wiki notes]]
+<br />
+Reproducible builds, byte-wise reproducible software:
+*  http://events.linuxfoundation.org/sites/events/files/slides/reproducible-build-zoo-elc.pdf
+*  https://labs.riseup.net/code/issues/14455
+Server Side services . . .
+<ul>
+Apache2 configuration:
+*  https://www.sslshopper.com/apache-redirect-http-to-https.html
+SSL
+*  [http://server.arcgis.com/en/web-adaptor/latest/install/iis/enable-https-on-your-web-server-server-.htm SSL certificates behind firewall]
+DNS
+*  [http://www.tldp.org/HOWTO/DNS-HOWTO.html DNS How-To] at [http://tlpd.org TLDP]
+*  [http://www.tldp.org/HOWTO/DNS-HOWTO.html DNS How-To by Nicolai Langfeldt]
+MYSQL
+*  [https://www.digitalocean.com/community/tutorials/how-to-install-mysql-on-ubuntu-16-04 Digital Ocean - How to install MYSQL tutorial]
+</ul>
+Coding standards:
+*  https://www.kernel.org/doc/html/latest/process/coding-style.html
+C and C++:
+*  https://www.tutorialspoint.com/cplusplus/cpp_variable_types.htm "A variable can be declared multiple times but defined only once in a file, routine or code block."
 Couple of MediaWiki and publishing issues to look into, which came up during wiki configuration:
-*  https://www.medihttps://alta-ubuntu.veris.com/wiki/index.php/Main_Pageawiki.org/wiki/Manual:User_rights
+*  https://www.mediawiki.org/wiki/Manual:User_rights
 *  https://creativecommons.org/licenses/by-sa/3.0/
 *  https://choosealicense.com/
 Some Hindi language and UTF-8 encoding references, to be factored to a dedicated wiki page later:
@@ Line 1,224: / Line 2,530: @@
 *  http://hindilearner.com/hindi_words_phrases/hindi_words_time_days.html
 *  http://www.learning-hindi.com/post/3072325702/lesson-91-%E0%A4%B8%E0%A4%AA-%E0%A4%A4-%E0%A4%B9-%E0%A4%95-%E0%A4%A6-%E0%A4%A8-days-of-the-week
 Linux programs and utilities:
@@ Line 1,230: / Line 2,537: @@
 *  [https://askubuntu.com/questions/390769/how-do-i-resize-partitions-using-command-line-without-using-a-gui-on-a-server resize2fs util to resize ext2, ext3, ext4 type partitions]
 *  [https://gcc.gnu.org/ml/gcc-help/2015-08/msg00104.html shell script 'runtest' provided by package dejagnu]
+Graphics Servers:
+*  https://www.reddit.com/r/linux/comments/4bq9kl/eli5_wayland_vs_mir_vs_x11/ X11 versus Wayland compositor
@@ Line 1,238: / Line 2,549: @@
 QEMU
 *  [https://www.raspberrypi.org/forums/viewtopic.php?t=175454 running virtual raspberrypi system using QEMU]
-*  [https://azeria-labs.com/emulate-raspberry-pi-with-qemu/ Azeria labs with more detailed steps to modifying image, not kernel, to boot fully in
+*  [https://azeria-labs.com/emulate-raspberry-pi-with-qemu/ Azeria labs with more detailed steps to modifying image, not kernel, to boot fully in QEMU]
-QEMU]
 *  [https://github.com/dhruvvyas90/qemu-rpi-kernel Dhruvvyas90 qemu-rpi-kernel]
+I2C
+*  https://www.nxp.com/docs/en/user-guide/UM10204.pdf
+Access iPhone via Linux
+*  https://www.maketecheasier.com/easily-mount-your-iphone-as-an-external-drive-in-ubuntu/
 <!-- comment -->
+== [[#top|^]] End of page ==
+&nbsp;<br />
+&nbsp;<br />
 <center>

Difference between revisions of "User:Ted"

Latest revision as of 22:38, 14 November 2024

OVERVIEW

^ Technology and Tools

^ temporary section

Contents

↑ ↓ Countries and politics

↑ ↓ Community, Culture, the World

↑ ↓ Geography and Place

↑ ↓ People

↑ ↓ Human languages

↑ ↓ Science

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↑ ↓ GNU Make and GCC Tools

↑ ↓ OpenOCD and Eagle set up notes

↑ ↓ Mediawiki Issues and Notes

^ File uploads

^ Images in wiki pages and image attributes

^ Mediawiki layout topics like multi column layout

^ Other Mediawiki topics

↑ ↓ Web Site Building Blocks - Summer 2017 to 2020 Q1 Work

↑ ↓ Open Source License Types

↑ ↓ Linux Packages (Separate Article)

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↑ ↓ Bash Shell Scripting

↑ ↓ edit point - shell variable quoting

↑ ↓ example shell script - back up several databases

↑ ↓ show kernel version script

↑ ↓ Other useful shell tutorial references

↑ ↓ Regex tutorials

↑ ↓ `sed` stream editor

↑ ↓ Other Computer Programming Languages

↑ ↓ Python Scripting Language

↑ ↓ Expect Utility by Don Libes

↑ ↓ edit point - Tool command language Tcl

↑ ↓ edit point - Tcl pattern matching and anchoring, symbols ^ and $ wrt data not lines

↑ ↓ Rust programming language

^ C programming notes

^ C++ references

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↑ ↓ Aboriginal Linux - project now defunct, new project is 'makeroot'

↑ ↓ Linux From Scratch (Separate Article)

↑ ↓ QEMU Emulator

↑ ↓ Embedded Linux Notes, focus on Rpi Linux Kernel Config

↑ ↓ FreeRTOS Notes (Separate Article)

↑ ↓ Bootloader U-Boot

↑ ↓ LPC11U6x Development Board

↑ ↓ avr-libc

↑ ↓ EWAVR, IAR Workbench, Keil compiler notes

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↑ ↓ Yocto References

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↑ ↓ Mobile App Development On Linux

↑ ↓ Android programming

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↑ ↓ Toradex embedded ARM computers

↑ ↓ Build U-boot and Linux kernel from source

↑ ↓ Arduino Development Kit and Documentation

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↑ ↓ Electronics

↑ ↓ tools and hardware

↑ ↓ measurement equipment

↑ ↓ Modbus protocol

↑ ↓ Mathematica

^ Books on mathematics

^ Fast Fourier Transform FFT

↑ ↓ Literature

↑ ↓ Other Things To Explore

^ DYI laptop by Olimex

↑ ↓ edit point

↑ ↓ edit point

↑ ↓ music and lyrics

↑ ↓ plant and animal references

^ Cacti

^ Agavacae

^ Nursurias

^ plant pathology

^ Technology History and Evolution

^ Astronomy

^ Food and Cooking