Commands tagged bash (821)
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My version uses printf and command substitution ($()) instead of echo -e and xargs, this is a few less chars, but not real substantive difference. Also supports lowercase hex letters and a backslash (\) will make it through unescaped Show Sample Output
3printf $(echo -n $1 | sed 's/\\/\\\\/g;s/\(%\)\([0-9a-fA-F][0-9a-fA-F]\)/\\x\2/g') -
The iostat command is used for monitoring system input/output device loading by observing the time the devices are active in relation to their average transfer rates. in ubuntu to get the iostat program do this: sudo apt-get install sysstat i found this command here: http://www.ocztechnologyforum.com/forum/showthread.php?t=54379 Show Sample Output
3iostat -m -d /dev/sda1 -
sed already has an option for editing files in place and making backup copies of the old file. -i will edit a file in place and if you give it an argument, it will make a backup file using that string as an extension.
3sed -i.bak 's/old/new/g' file -
I use this command (PS1) to show a list bash prompt's special characters. I tested it against A flavor of Red Hat Linux and Mac OS X Show Sample Output
3alias PS1="man bash | sed -n '/ASCII bell/,/end a sequence/p'" -
The loop is to compare cookies. You can remove it... Maybe you wanna use curl...
curl www.commandlinefu.com/index.php -s0 -I | grep "Set-Cookie"3a="www.commandlinefu.com";b="/index.php";for n in $(seq 1 7);do echo -en "GET $b HTTP/1.0\r\nHost: "$a"\r\n\r\n" |nc $a 80 2>&1 |grep Set-Cookie;done -
3newest () { find ${1:-\.} -type f |xargs ls -lrt ; }
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3cat *.txt >output.txt
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One of my favorite ways to impress newbies (and old hats) to the power of the shell, is to give them an incredibly colorful and amazing version of the top command that runs once upon login, just like running fortune on login. It's pretty sweet believe me, just add this one-liner to your ~/.bash_profile -- and of course you can set the height to be anything, from 1 line to 1000!
G=$(stty -g);stty rows $((${LINES:-50}/2));top -n1; stty $G;unset GDoesn't take more than the below toprc file I've added below, and you get all 4 top windows showing output at the same time.. each with a different color scheme, and each showing different info. Each window would normally take up 1/4th of your screen when run like that - TOP is designed as a full screen program. But here's where you might learn something new today on this great site.. By using the stty command to change the terminals internal understanding of the size of your terminal window, you force top to also think that way as well. # save the correct settings to G var.G=$(stty -g)# change the number of rows to half the actual amount, or 50 otherwisestty rows $((${LINES:-50}/2))# run top non-interactively for 1 second, the output stays on the screen (half at least)top -n1# reset the terminal back to the correct values, and clean up after yourselfstty $G;unset GThis trick from my [ http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html bash_profile ], though the online version will be updated soon. Just think what else you could run like this! Note 1: I had to edit the toprc file out due to this site can't handle that (uploads/including code). So you can grab it from [ http://www.askapache.com/linux-unix/bash-power-prompt.html my site ] Note 2: I had to come back and edit again because the links weren't being correctly parsed Show Sample Output3G=$(stty -g);stty rows $((${LINES:-50}/2));top -n1; stty $G;unset G -
Gives you a list for all installed chrome (chromium) extensions with URL to the page of the extension. With this you can easy add a new Bookmark folder called "extensions" add every URL to that folder, so it will be synced and you can access the names from every computer you are logged in. ------------------------------------------------------------------------------------------------------------------ Only tested with chromium, for chrome you maybe have to change the find $PATH. Show Sample Output
3for i in $(find ~/.config/chromium/*/Extensions -name 'manifest.json'); do n=$(grep -hIr name $i| cut -f4 -d '"'| sort);u="https://chrome.google.com/extensions/detail/";ue=$(basename $(dirname $(dirname $i))); echo -e "$n:\n$u$ue\n" ; done -
Once you get into advanced/optimized scripts, functions, or cli usage, you will use the sort command alot. The options are difficult to master/memorize however, and when you use sort commands as much as I do (some examples below), it's useful to have the help available with a simple alias. I love this alias as I never seem to remember all the options for sort, and I use sort like crazy (much better than uniq for example). # Sorts by file permissions
find . -maxdepth 1 -printf '%.5m %10M %p\n' | sort -k1 -r -g -bS 20%00761 drwxrw---x ./tmp 00755 drwxr-xr-x . 00701 drwx-----x ./askapache-m 00644 -rw-r--r-- ./.htaccess # Shows uniq history fasthistory 1000 | sed 's/^[0-9 ]*//' | sort -fubdS 50%exec bash -lxv export TERM=putty-256color Taken from my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html Show Sample Output3alias sorth='sort --help|sed -n "/^ *-[^-]/s/^ *\(-[^ ]* -[^ ]*\) *\(.*\)/\1:\2/p"|column -ts":"' -
This shows every bit of information that stat can get for any file, dir, fifo, etc. It's great because it also shows the format and explains it for each format option. If you just want stat help, create this handy alias 'stath' to display all format options with explanations.
alias stath="stat --h|sed '/Th/,/NO/!d;/%/!d'"To display on 2 lines:( F=/etc/screenrc N=c IFS=$'\n'; for L in $(sed 's/%Z./%Z\n/'<<<`stat --h|sed -n '/^ *%/s/^ *%\(.\).*$/\1:%\1/p'`); do G=$(echo "stat -$N '$L' \"$F\""); eval $G; N=fc;done; )For a similarly powerful stat-like function optimized for pretty output (and can sort by any field), check out the "lll" function http://www.commandlinefu.com/commands/view/5815/advanced-ls-output-using-find-for-formattedsortable-file-stat-info From my .bash_profile -> http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html Show Sample Output3statt(){ C=c;stat --h|sed '/Th/,/NO/!d;/%/!d'|while read l;do p=${l/% */};[ $p == %Z ]&&C=fc&&echo ^FS:^;echo "`stat -$C $p \"$1\"` ^$p^${l#%* }";done|column -ts^; } -
If a tmux session is already running attach it, otherwise create a new one. Useful if you often forget about running tmuxes (or just don't care)
3alias ltmux="if tmux has; then tmux attach; else tmux new; fi" -
Another alternative is to define a function: lower() { echo ${@,,} } lower StrinG Show Sample Output
3s="StrinG"; echo ${s,,} -
Uses vi style search / replace in bash to rename files. Works with regex's too (I use the following a script to fixup / shorten file names): # Remove complete parenthetical/bracket/brace phrases rename 's/\(.*\)//g' * rename 's/\[.*\]//g' * rename 's/\{.*\}//g' * Show Sample Output
3rename 's/foo/bar/g' foobar -
If the return code from the last command was greater than zero, colour part of your prompt red. The commands give a prompt like this: [user current_directory]$ After an error, the "[user" part is automatically coloured red. Tested using bash on xterm and terminal. Place in your .bashrc or .bash_profile.
3export PROMPT_COMMAND='if (($? > 0)); then echo -ne "\033[1;31m"; fi'; export PS1='[\[\]\u\[\033[0m\] \[\033[1;34m\]\w\[\033[0m\]]\$ ' -
enable each bash completion that you have installed at your system, that's very nice ;)
3for x in $(eselect bashcomp list | sed -e 's/ //g' | cut -d']' -f2 | sed -e 's/\*//');do eselect bashcomp enable $x --global;sleep 0.5s;done -
Similar to xargs -i, but works with builtin bash commands (rather than running "bash -c ..." through xargs)
3xargsb() { while read -r cmd; do ${@//'{}'/$cmd}; done; } -
Logs all users out except root. I changed the grep to use a regexp in case a user's username contained the word root.
3who -u | grep -vE "^root " | kill `awk '{print $7}'` -
Ruby version. Also, a perl version:
perl -e 'printf("%.2x.",rand(255))for(1..5);printf("%.2x\n",rand(255))'3ruby -e 'puts (1..6).map{"%0.2X"%rand(256)}.join(":")' -
1. you don't need to prepend the year with 20 - just use Y instead of y 2. you may want to make your function a bit more secure: buf () { cp ${1?filename not specified}{,$(date +%Y%m%d_%H%M%S)}; }
3buf () { cp $1{,$(date +%Y%m%d_%H%M%S)}; } -
Bash alias for easy irssi within screen, attempts to attach to existing irssi session, if one exists, otherwise creates one - Including wipe for when system reboots and leaves "dead" session.
3alias irssi="screen -wipe; screen -A -U -x -R -S irssi irssi" -
3bargs { while read i; do "$@" "$i"; done }
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Also looks in subfolders
3find . | shuf -n1 -
Alternatively: export MyVAR=84; awk '{ print ENVIRON["MyVAR"] }'
3MyVAR=85 awk '{ print ENVIRON["MyVAR"] }' -
background and disown, but with a proper one-line syntax
3^z; bg; disown - ‹ First < 8 9 10 11 12 > Last ›
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