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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
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Commands using exit from sorted by
Terminal - Commands using exit - 17 results
curlh() { x="$(curl -Is -w '%{http_code}' "$@")"; if [[ "$(tail -n 1 <<< "$x")" == [45]* ]]; then curl -is "$@" | awk '{ if (!NF) { exit }; print }'; else head -n -1 <<< "$x"; fi; }
2017-07-10 12:29:00
User: nyuszika7h
Functions: awk exit head

Some sites running on basic web servers don't support the HEAD request, so using "curl -I" on them doesn't work. This will automatically try "curl -I" at first and if that fails with a 4xx or 5xx status code, it falls back to "curl -i" and prints only the headers from that.

perl -MFile::Find=find -MFile::Spec::Functions -Tlwe '$found=1; find { wanted => sub { if (/$ARGV[0]\.pm\z/) { print canonpath $_; $found=0; } }, no_chdir => 1 }, @INC; exit $found;' Collectd/Plugins/Graphite
2013-01-11 11:01:46
User: keymon
Functions: exit find perl

Will check if the given module is installed in the @INC. It will print the path and return 0 if found, or 1 otherwise.

Based on script from SharpyWarpy in http://www.linuxquestions.org/questions/linux-general-1/how-to-list-all-installed-perl-modules-216603/

cat /dev/urandom|od -t x1|awk 'NR > line { pos=int(rand()*15)+2;printf("%s",$pos);line=NR+(rand()*1000);digits = digits+2 } digits == 64 { print("\n");exit }'
2012-08-14 19:02:00
User: jetdillo
Functions: awk cat exit od

Use this the next time you need to come up with a reasonably random bitstring, like for a WPA/WPA2 PSK or something. Takes a continuous stream of bytes coming from /dev/urandom, runs it through od(1), picking a random field ($0 and $1 excluded) from a random line and then prints it.

die_msg() { echo $@ >&2; exit -1; }
2012-02-24 04:06:04
User: admon
Functions: echo exit

Using a standard way to handle error message and return code.

for c in gcc bison dialog bc asdf; do if ! which $c >/dev/null; then echo Required program $c is missing ; exit 1; fi; done
<command> >NUL 2>&1 || ( echo <Command> not found. Please install <command> or check PATH variable! & pause & exit )
2011-03-07 14:27:42
User: Marco
Functions: echo exit install
Tags: windows batch dos

This is a command to be used inside of MS-DOS batch files to check existence of commands as preconditions before actual batch processing can be started. If the command is found, batch script continues execution. If not, a message is printed on screen, script then waits for user pressing a key and exits.

An error message of the command itself is suppressed for clarity purpose.

if [ -z "${BASH_VERSINFO}" ] || [ -z "${BASH_VERSINFO[0]}" ] || [ ${BASH_VERSINFO[0]} -lt 4 ]; then echo "This script requires Bash version >= 4"; exit 1; fi
2011-02-25 11:02:47
User: hfs
Functions: echo exit
Tags: bash version

If you use new features of a certain Bash version in your shell script, make sure that it actually runs with the required version.

package=$1; list=/var/lib/dpkg/info/${package}.list; inst=$(stat "$list" -c %X); cat $list | (while read file; do if [ -f "$file" ];then acc=$(stat "$file" -c %X); if [ $inst -lt $acc ]; then echo used $file; exit 0; fi; fi; done; exit 1)
2010-09-20 18:10:19
User: pipeliner
Functions: cat echo exit read stat
Tags: apt dpkg date stat

This script compares the modification date of /var/lib/dpkg/info/${package}.list and all the files mentioned there.

It could be wrong on noatime partitions.

Here is non-oneliner:




inst=$(stat "$list" -c %X);

cat $list |


while read file; do

if [ -f "$file" ]; then

acc=$(stat "$file" -c %X);

if [ $inst -lt $acc ]; then

echo used $file

exit 0




exit 1


echo "${1}" | egrep '^[[:digit:]]*$' ; if [ "$?" -eq 0 ] ; then sed -i "${1}"d $HOME/.ssh/known_hosts ; else printf "\tYou must enter a number!\n\n" ; exit 1 ; fi
2010-07-11 23:09:11
User: DaveQB
Functions: echo egrep exit printf sed
Tags: sed

I have this as a file called deletekey in my ~/bin.

Makes life a little easier.

bsro3 () { P=`pwd`; S=$1; R=$2; ls *.odt > /dev/null 2>&1; if [[ $? -ne 0 ]]; then exit 1; fi; for i in *.odt; do mkdir ${P}/T; cd ${P}/T; unzip -qq "$P"/"$i"; sed -i "s/$S/$R/" ${P}/T/content.xml; zip -qq -r "$P"/"$i" *; cd ${P}; rm -rf ${P}/T; done; }
2010-06-30 04:43:54
User: danpos
Functions: cd exit ls mkdir rm sed

This function does a batch edition of all OOO3 Writer files in current directory. It uses sed to search a FOO pattern into body text of each file, then replace it to foo pattern (only the first match) . I did it because I've some hundreds of OOO3 Writer files where I did need to edit one word in each ones and open up each file in OOO3 gui wasn't an option. Usage: bsro3 FOO foo

cmd=$(wget -qO- "http://www.m-w.com/dictionary/$(echo "$@"|tr '[A-Z]' '[a-z]')" | sed -rn "s#return au\('([^']+?)', '([^'])[^']*'\);.*#\nwget -qO- http://cougar.eb.com/soundc11/\2/\1 | aplay -q#; s/[^\n]*\n//p"); [ "$cmd" ] && eval "$cmd" || exit 1
2010-03-12 13:56:41
User: hackerb9
Functions: eval exit sed wget

Looks up a word on merriam-webster.com, does a screen scrape for the FIRST audio pronunciation and plays it.

USAGE: Put this one-liner into a shell script (e.g., ~/bin/pronounce) and run it from the command line giving it the word to say:

pronounce lek

If the word isn't found in merriam-webster, no audio is played and the script returns an error value. However, M-W is a fairly complete dictionary (better than howjsay.com which won't let you hear how to pronounce naughty words).

ASSUMPTIONS: GNU's sed (which supports -r for extended regular expressions) and Linux's aplay. Aplay can be replaced by any program that can play .WAV files from stdin.

KNOWN BUGS: only the FIRST pronunciation is played, which is problematic if you wanted a particular form (plural, adjectival, etc) of the word. For example, if you run this:

pronounce onomatopoetic

you'll hear a voice saying "onomatopoeia".

Playing the correct form of the word is possible, but doing so might make the screen scraper even more fragile than it already is. (The slightest change to the format of m-w.com could break it).

xmlproc_parse.python-xml &>/dev/null <FILE> || exit 1
2009-12-11 17:30:03
User: sputnick
Functions: exit
Tags: python xml

For debian likes, that's in python-xml package.

xmllint --noout some.xml 2>&1 >/dev/null || exit 1
[ -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.)

[ -z "$VAR" ] && echo "VAR has not been set" && exit 1
TMPROOT=/tmp; TMPDIR=$(mktemp -d $TMPROOT/somedir.XXXXXX); TMPFILE=$(mktemp $TMPROOT/somefile.XXXXXX); trap "rm -rf $TMPDIR $TMPFILE; exit" INT TERM EXIT; some treatment using $TMPDIR and $TMPFILE; exit 0
2009-02-24 09:35:22
User: raphink
Functions: exit mktemp trap

Cleanly create tempfiles using mktemp and remove them using traps instead of removing them in the end of the script. This way, you make sure the tempfiles are removed properly even if the script is killed or interrupted.

For a user script in KDE4, you can set TMPROOT using :

TMPROOT=$(kde4-config --path tmp)