Commands tagged shell function (6)

  • Display all shell functions set in the current shell environment

    Uses the shell builtin `declare` with the '-f' flag to output only functions to grep out only the function names. You can use it as an alias or function like so: alias shfunctions="builtin declare -f | command grep --color=never -E '^[a-zA-Z_]+\ \(\)'" shfunctions () { builtin declare -f | command grep --color=never -E '^[a-zA-Z_]+\ \(\)'; } Show Sample Output


    2
    builtin declare -f | command grep --color=never -E '^[a-zA-Z_]+\ \(\)'
    sciro · 2018-07-23 05:24:04 1095
  • command shell generate random strong password

    shell generate random strong password Show Sample Output


    2
    len=20; tr -dc A-Za-z0-9_ < /dev/urandom | head -c ${len} | xargs
    aysadk · 2019-04-16 20:20:46 39
  • Extract content between the first " and the last " double quotes

    Thanks to this user: https://stackoverflow.com/a/35636373/2394635 Show Sample Output


    1
    s='Test "checkin_resumestorevisit \"- "Online_V2.mt" Run'; s=${s#*'"'}; s=${s%'"'*}; echo "$s"
    bugmenot · 2022-01-08 16:16:18 506
  • ..(), go up in directory tree, func to long please refer to description

    many have aliases like: alias ...="cd ../../" alias ....="cd ../../../" and so furth. ..() mitigates to need for those aliases, see sample output for an example # .. -> go up 1 directory # .. 4 -> go up 4 directories ..() { local DIR='' declare -i NUM=0 if [[ ${1} =~ ^[1-9][0-9]*$ ]] then while (( ${NUM} < ${1:-1} )) do DIR="${DIR}../" NUM=$(( ${NUM} + 1 )) done else DIR=.. fi cd "${DIR}" } Show Sample Output


    -4
    [ ~/temp/foo/bar/baz ] $ .. 3
    Xk2c · 2015-01-01 20:41:17 10
  • check4progs(), func to long please refer to description

    Thanks to the great grml team for this func! You really should look at their shell configs for further usefull things! http://git.grml.org/?p=grml-etc-core.git;a=blob_plain;f=etc/grml/script-functions;h=4d6bcea8f9beae83abd08f44155d299ea54a4a9f;hb=HEAD # {{{ check for availability of program(s) # usage example: # check4progs [-s,-q,--quiet,--silent] arg [arg .... argn] # # with option given either of: # -s,-q,--quiet,--silent # # check for available progs but produce no output check4progs() { [ -n "${ZSH_VERSION}" ] && emulate -L sh local RTN=0 local oldifs="${IFS}" local ARG d found local VERBOSE=1 case ${1} in -q | -s | --quiet | --silent) VERBOSE=0 shift 1 ;; *) ;; esac while [ $# -gt 0 ] do ARG="$1" shift found=0 IFS=: for d in $PATH do if [ -x "${d}/${ARG}" ] then found=1 break fi done IFS="${oldifs}" # check for availability if [ ${found} -eq 0 ] then if [ ${VERBOSE} -eq 1 ] then printf "%s: binary not found\n" "${ARG}" >&2 fi RTN=1 fi done # return non zero, if at least one prog is missing! return $RTN } # }}} Show Sample Output


    -6
    $ if check4progs cp foo mv bar rsync; then echo "needed progs avail, lets do funky stuff"; else echo "oh oh better abort now"; fi
    Xk2c · 2015-01-01 16:16:00 8
  • cd(), do a ls (or whatever you can imagine) after a cd, func to long please refer to description

    some people on the net already use a cd(), but most of them break 'cd -' functionality, that is "go back where you have been previosly", or 'cd' which is "go back home". This cd() copes with that. Also when given a file name, go to the directory where this file is in. cd() { if [[ -n ${*} ]] then if [[ s${*}e == s-e ]] then builtin cd - elif [[ ! -d ${*} ]] then builtin cd "${*%/*}" else builtin cd "${*}" fi else builtin cd ~ fi ls -la }


    -6
    cd(), do a ls (or whatever you can imagine) after a cd, func to long please refer to description
    Xk2c · 2015-01-01 20:50:19 9

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A fun thing to do with ram is actually open it up and take a peek. This command will show you all the string (plain text) values in ram
cat? dd? RTFM

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Mac OS X: remove extra languages to save over 3 GB of space.
This will get the job done in the most efficient way - spawning only one `rm` process. "On-the-fly" find data is displayed through `tee` and you should have plenty of time to ctrl-c if needed before it's too late. You may need to re-run this after major Software Updates. To leave more languages in, add more ``-and \! -iname "lang*"'' statements: $ sudo find / -iname "*.lproj" -and \! -iname "en*" -and \! -iname "spanish*" -print0 | tee /dev/stderr | sudo xargs -0 rm -rfv **Edit: note the 2nd sudo near the end of the pipeline - this is necessary.

Remove empty directories
You can also use, $ find . -depth -type d -exec rmdir {} \; 2>/dev/null

Alias TAIL for automatic smart output
Run the alias command, then issue $ps aux | tail and resize your terminal window (putty/console/hyperterm/xterm/etc) then issue the same command and you'll understand. $ ${LINES:-`tput lines 2>/dev/null||echo -n 12`} Insructs the shell that if LINES is not set or null to use the output from `tput lines` ( ncurses based terminal access ) to get the number of lines in your terminal. But furthermore, in case that doesn't work either, it will default to using the default of 80. The default for TAIL is to output the last 10 lines, this alias changes the default to output the last x lines instead, where x is the number of lines currently displayed on your terminal - 7. The -7 is there so that the top line displayed is the command you ran that used TAIL, ie the prompt. Depending on whether your PS1 and/or PROMPT_COMMAND output more than 1 line (mine is 3) you will want to increase from -2. So with my prompt being the following, I need -7, or - 5 if I only want to display the commandline at the top. ( http://www.askapache.com/linux/bash-power-prompt.html ) 275MB/748MB [7995:7993 - 0:186] 06:26:49 Thu Apr 08 [askapache@n1-backbone5:/dev/pts/0 +1] ~ $ In most shells the LINES variable is created automatically at login and updated when the terminal is resized (28 linux, 23/20 others for SIGWINCH) to contain the number of vertical lines that can fit in your terminal window. Because the alias doesn't hard-code the current LINES but relys on the $LINES variable, this is a dynamic alias that will always work on a tty device.

revert a file with svn

Convert filenames from ISO-8859-1 to UTF-8
Nothing advanced, it just finds filenames that are stored with ISO-8859-1 characters and and converts those into UTF-8. Recommended to use without the --notest flag first so you can see what will be changed.

Start another X session in a window
You might have Xnest (older) rather than Xephyr. You can experiment with other desktops eg: startx /usr/bin/start-kde -- /usr/bin/Xephyr :2 You can start X on a remote machine (although I'd recommend vnc for anything slower than a LAN): startx /usr/bin/ssh -X gnome-session -- /usr/bin/Xephyr :2 Or just start another X session locally talking to the remote backend:

diff directories, quick cut and paste to view the changes
We use this to quickly highlight differences and provide a quick way to cut and paste the command to view the files using the marvellous vimdiff

Diff 2 file struct - Useful for branch diff and jars diff(uncompressed)
This is usefull to diff 2 paths in branches of software, or in different versions of a same zip file. So you can get the real file diff.

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