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May 19, 2015 - A Look At The New Commandlinefu
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Commands tagged bash from sorted by
Terminal - Commands tagged bash - 733 results
if tmux has; then tmux attach -d; else tmux new; fi
2013-02-15 14:29:15
User: Casey
Tags: bash alias sh tmux

Also detaches session if attached from somewhere else.

diff -u <(grep -vE '^(#|$)' file1) <(grep -vE '^(#|$)' file2)
2013-02-12 13:59:39
Functions: diff grep

Runs a diff on two files ignore comments and blank lines (diff -I=RE does not work as expected). Adapted from a post found on stackexchange.

color()(set -o pipefail;"$@" 2>&1>&3|sed $'s,.*,\e[31m&\e[m,'>&2)3>&1
sort file.txt | uniq -c | sort -k1nr -k2d
2013-01-28 22:21:05
User: westonruter
Functions: sort uniq
Tags: bash sorting

I used to do this sorting with:

sort file.txt | uniq -c | sort -nr

But this would cause the line (2nd column) to be sorted in descending (reverse) order as well sa the 1st column. So this will ensure the 2nd column is in ascending alphabetical order.

find-duplicates () { find "$@" -not -empty -type f -printf "%s\0" | sort -rnz | uniq -dz | xargs -0 -I{} -n1 find "$@" -type f -size {}c -print0 | xargs -0 md5sum | sort | uniq -w32 --all-repeated=separate; }
2013-01-23 23:20:26
User: mpeschke
Functions: find md5sum sort uniq xargs

This is a modified version of the OP, wrapped into a bash function.

This version handles newlines and other whitespace correctly, the original has problems with the thankfully rare case of newlines in the file names.

It also allows checking an arbitrary number of directories against each other, which is nice when the directories that you think might have duplicates don't have a convenient common ancestor directory.

perl -MModule::Name\ 9999 -e 1
2013-01-15 22:51:39
User: three18ti
Functions: perl
Tags: bash perl zsh

This attempts to load a Perl Module (-M flag) and use version 9999, since no module has a version this high, Perl exits either a) telling you the version of the module installed or b) tells you it can't find the module.

for code in $(seq -w 0 255); do for attr in 0 1; do printf "%s-%03s %bTest%b\n" "${attr}" "${code}" "\e[${attr};38;05;${code}m" "\e[m"; done; done | column -c $((COLUMNS*2))
2013-01-13 18:23:44
User: claudius
Functions: column printf seq
Tags: bash color colors

Shows the ?rendering? for each of the 256 colours in both the bold and normal variant. Using seq is helpful to get even lines, passing $((COLUMNS*2)) to column sort-of-handles the nonprintable characters.

perldoc -l Module::Name 2>/dev/null
2013-01-11 23:28:13
User: MarxBro
Tags: bash perl

Shows the path if the module is installed or exit quietly (to simply avoid the 'No documentation found' msg).

module_exists(){ perl -e 'use '$1 2>/dev/null; }
2013-01-11 14:47:07
User: putnamhill
Functions: perl
Tags: bash perl

This version uses a bash function and does not print the path to the module.

curl http://en.wikipedia.org/wiki/List_of_programming_languages | grep "<li>" | awk -F"title=" '{ print $2 }' | awk -F\" '{ print $2 }'
2013-01-09 21:40:11
User: sxiii
Functions: awk grep

Requirements: curl, grep, awk, internet connection with access to wikipedia

Loaded page: http://en.wikipedia.org/wiki/List_of_programming_languages

If you can make shorter version of this listgetter, you are welcome to paste it here :)

while sleep 1; do (mpc status;mpc currentsong)|awk 'BEGIN{FS=": "}/^Artist:/{r=r""$2};/^Title:/{r=r" - "$2};/^time:/{r=$2" "r};/^state: play/{f=1}END{if(f==1){print r}}'|echo -ne "\e[s\e[0;0H\e[K\e[0;44m\e[1;33m$(cat -)\e[0m\e[u";done &
2012-12-24 18:03:29
User: ichbins
Functions: awk echo sleep
Tags: bash mpd,

Actually this is a shorter version that fits the 255 chars limit of this resource. The full version shows status in the right top corner:

alias mpdd='while sleep 1; do _r=$(awk '\''BEGIN{FS=": "}/^Artist:/{r=r""$2};/^Title:/{r=r" - "$2};/^time:/{r=$2" "r};/^state: play/{f=1}END{if(f==1){print r}}'\'' <(mpc status;mpc currentsong));_l=${#_r};[ $_l -eq 0 ] && continue;[ -z "$_p" ] && _p=$_l;echo -ne "\e[s\e[0;${_p}H\e[K\e[u";_p=$((COLUMNS - _l));echo -ne "\e[s\e[0;${_p}H\e[K\e[0;44m\e[1;33m${_r}\e[0m\e[u";done &'

mpc is defined like this:

function mpc() {

echo "$*" | nc 6600


exipick -zi | xargs --max-args=1000 exim -Mrm
2012-12-12 20:46:22
User: jasen
Functions: xargs
Tags: bash awk exim

do 1000 at a time so that if your doodoo is deep you can avoid avoid "command-line too big" error

for i in `eselect bashcomp list | awk '{print $2}'`; do eselect bashcomp enable $i; done
diff <(cd dir1 && find . | sort) <(cd dir2 && find . | sort)
tmux attach || tmux new
while true; do printf "\e[32m%X\e[0m" $((RANDOM%2)); for ((i=0; i<$((RANDOM%128)); i++)) do printf " "; done; done
2012-11-27 10:40:42
User: seb1245
Functions: printf

Unlike other alternatives, this command only relies on bash builtins and should also work on windows platforms with the bash executable.

Sparseness corresponds to the number 128 and can be adjusted. To print all possible digits instead of only 0 and 1 replace RANDOM%2 by RANDOM%10 or RANDOM%16 to add letters [A-F].

trash <file>
2012-11-22 18:05:11
User: bkmeneguello
Tags: bash trash rm

# put into .bashrc

function trash() {

if [ -z "$*" ] ; then

echo "Usage: trash filename"


local TRASH="${HOME}/.local/share/Trash"

if [ ! -d "$TRASH/files" ]; then mkdir -p "$TRASH/files"; fi

if [ ! -d "$TRASH/info" ]; then mkdir -p "$TRASH/info"; fi

local IFS_BKP=$IFS



for FILE in $@ ; do

local BASE=$( basename "$FILE" )


local COUNTER=1

while [ -e "$TRASH/files/$TRASH_NAME" ]; do




local FULL_PATH=$( readlink -f "$FILE" )

local DATE=$( date +%Y-%m-%dT%H:%M:%S )


if [ $? -eq 0 ]; then

echo "[Trash Info]


DeletionDate=$DATE" > "$TRASH/info/$TRASH_NAME.trashinfo"






function emon { emacs "$1" --eval '(auto-revert-tail-mode)' --eval '(setq buffer-read-only t)' --eval '(goto-char (point-max))' }
2012-11-21 17:24:27
User: wytten12
Functions: emacs
Tags: bash emacs

Monitoring a log file with 'tail -f' is handy, but for emacs users monitoring the file with emacs is even better, because you can use all your familiar key bindings for copying regions, etc.

echo $((RANDOM % 10 + 1))
2012-11-21 13:49:53
User: putnamhill
Functions: echo
Tags: bash

If you don't have seq or shuf, bash can be used.

export HISTSIZE=0
ctrl-x ctrl-x
telnet 0 <port>
2012-11-16 03:38:49
User: somaddict
Functions: telnet

Super fast way to ftp/telnet/netcat/ssh/ping your loopback address for testing. The default route is simply reduced to 0.

for host in $HOSTNAMES; do ping -q -c3 $host && ssh $host 'command' & for count in {1..15}; do sleep 1; jobs | wc -l | grep -q ^0\$ && continue; done; kill %1; done &>/dev/null
for host in $MYHOSTS; do ping -q -c3 $H 2>&1 1>/dev/null && ssh -o 'AllowedAuthe ntications publickey' $host 'command1; command2' & for count in 1 2 3 4 5; do sleep 1; jobs | wc -l | grep -q ^0\$ && continue; done; kill %1; done
2012-11-13 23:12:27
User: a8ksh4
Functions: grep host jobs kill ping sleep ssh wc

Execute commands serially on a list of hosts. Each ssh connection is made in the background so that if, after five seconds, it hasn't closed, it will be killed and the script will go on to the next system.

Maybe there's an easier way to set a timeout in the ssh options...

cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 18 | head -1 | python -c "import sys,crypt; stdin=sys.stdin.readline().rstrip('\n'); print stdin;print crypt.crypt(stdin)"
2012-11-09 00:40:22
User: cnyg
Functions: cat fold head python tr

Generate a 18 character password from character set a-zA-Z0-9 from /dev/urandom, pipe the output to Python which prints the password on standard out and in crypt sha512 form.