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--- tools:shell [2023/09/19 10:09] – removed - external edit (Unknown date) 127.0.0.1
+++ tools:shell [2026/07/01 12:16] (current) – [Tutorials] will
@@ Line 1: / Line 1: @@
+====== Shell ======
+eg. ''bash'' (''sh'' but "bourne" again), ''zsh'' (default for macOS), ''tcsh'' (NIH favorite)
+===== Tutorials =====
+  * https://www.tutorialspoint.com/unix/index.htm starts super super basic but covers advance topics (via Orma)
+  * https://seankross.com/the-unix-workbench/command-line-basics.html
+  * https://missing.csail.mit.edu/2020/shell-tools/ via Warren
+  * https://www.learnshell.org/ (via Amar)
+  * [[https://afni.nimh.nih.gov/pub/dist/doc/htmldoc/educational/unix_tutorial/index.html|AFNI's unix intro]] to scripting
+  * [[https://andysbrainbook.readthedocs.io/en/latest/unix/Unix_Intro.html|Andy's brain blog book unix chapter]] includes videos
+  * Pitt's [[https://crc.pitt.edu/|center for research computing]] suggests
+    * https://cvw.cac.cornell.edu/Linux/default
+    * https://software-carpentry.org/lessons/
+==== Readline Keyboard Shortcut reference ====
+ https://readline.kablamo.org/emacs.html
+===== Utilities =====
+fzf, fasd (z), readline editing options, alt+., ctrl+r, [[https://github.com/WillForan/fuzzy_arg|fuzzy ctrl+r, alt+n newfiles]]
+===== Idioms  =====
+short if-statements. short form function definitions. regexp w/BASH_REMATCH
+<code=bash>
+if [ -r file.txt ]; then
+  rm file.txt
+fi
+# same as
+[ -r file.txt ] && rm file.txt
+# same as
+test -r file.txt && rm "$_"
+####
+function abc {
+  echo abc
+}
+# same as
+abc(){ echo abc; }
+###
+foobar="a1 b2 c3"
+[[ $foobar =~ c.* ]] && echo $BASH_REMATCH # c3
+</code>
+===== Input Arguments =====
+Both functions and scripts take "input arguments": what's provided to the right of the script or function.
+''"$#"'' is number input args, ''"$*"'' is all as single string ''"$@"'' is each argument quoted
+''$1'' .. ''$9'' are input arguments 1 to 9 (('$0' is the scripts name, ''$FUNCNAME'' is the current function)). ''printf'' like ''echo'' but first argument is how to format what follows
+<code=bash>
+nargs()    { echo  "$#"; }
+arg_at()   { nargs "$@"; }
+arg_star() { nargs "$*"; }
+arg_at   a b c # 3
+arg_star a b c # 1
+second()   { printf "*%s*\n" "$2"; }
+arg_at2()  { second "$@"; }
+arg_star2(){ second "$*"; }
+arg_at2   a b c # *b*
+arg_star2 a b c # **
+</code>