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2011-03-12 - Confoo 2011 presentation
Slides are available from the commandlinefu presentation at Confoo 2011: http://presentations.codeinthehole.com/confoo2011/
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Terminal - All commands - 11,585 results
rm strangedirs -rf
2009-06-30 15:10:31
User: ioggstream
Functions: rm
Tags: rm safe
-3

avoid rm to be recursive until you complete the command: put the -rf at the end!

less file.lst | head -n 50000 > output.txt
2011-09-05 05:26:04
User: Richie086
Functions: head less
-3

Useful for situations where you have word lists or dictionaries that range from hundreds of megabytes to several gigabytes in size. Replace file.lst with your wordlist, replace 50000 with however many lines you want the resulting list to be in total. The result will be redirected to output.txt in the current working directory. It may be helpful to run wc -l file.lst to find out how many lines the word list is first, then divide that in half to figure out what value to put for the head -n part of the command.

find `pwd` -type f \( -iname thumb.php -or -iname timthumb.php \) -exec grep -HP 'define ?\(.VERSION' {} \;
2011-12-27 11:33:54
User: djkee
Functions: find grep
-3

Good for finding outdated timthumb.php scripts which need to be updated, anything over 2.0 should be secure, below that timthimb is vulnerable and can be used to compromise your website.

ifconfig | grep "inet addr" | cut -d":" -f2 | cut -d" " -f1
lspci
svn revert .
play $audio_file
2009-03-17 11:30:02
User: mpb
-3

"play" is part of "SoX"

SoX - Sound eXchange, the Swiss Army knife of audio manipulation.

For details, see: man sox

O=$IFS;IFS=$'\n'; D=$(for f in *;do [[ -d $f ]] && du -sh "$f";done | sort -gr);F=$(for f in *;do [[ -f $f ]] && du -sh "$f";done | sort -gr);IFS=$O;echo "$D";echo "$F"
2009-09-03 11:39:50
User: Viperlin
Functions: du sort
-3

biggest->small directories, then biggest->smallest files

function duf { du -k $@ | sort -rn | perl -ne '($s,$f)=split(/\t/,$_,2);for(qw(K M G T)){if($s<1024){$x=($s<10?"%.1f":"%3d");printf("$x$_\t%s",$s,$f);last};$s/=1024}' }
vim file1 file2
echo -e '#!/bin/bash\nssh remote-user@remote-host $0 "$@"' >> /usr/local/bin/ssh-rpc; chmod +x /usr/local/bin/ssh-rpc; ln -s hostname /usr/local/bin/ssh-rpc; hostname
2011-12-28 17:43:34
User: mechmind
Functions: chmod echo hostname ln
Tags: ssh rpc
-3

It's useful mostly for your custom scripts, which running on specific host and tired on ssh'ing every time when you need one simple command (i use it for update remote apt repository, when new package have to be downloaded from another host).

Don't forget to set up authorization by keys, for maximum comfort.

taskkill /F /im notepad.exe
w: !mailx -s "Some subject" user@host.com
(set -e; while true; do TEST_COMMAND; done) | tee log
2011-09-06 12:29:11
User: wipu
Functions: set tee
Tags: tee while set
-3

If you need to fix a randomly failing test (race condition), you need to run it until you get that hard-to-reproduce failure.

ssh remotehosts;date
2012-11-09 01:14:24
User: kiiwii
Functions: ssh
-3

Run this within a steady screen session.

You can get the approximate time when the remote server went down or other abnormal behavior.

find /dev/ -name random -exec bash -c '[ -r $0 -a -w $0 ] && dd if=$0 | sort | dd of=$0' {} \;
dpkg-query -l| grep -v "ii " | grep "rc " | awk '{print $2" "}' | tr -d "\n" | xargs aptitude purge -y
2009-04-28 19:25:53
User: thepicard
Functions: awk grep tr xargs
-3

This will, for an application that has already been removed but had its configuration left behind, purge that configuration from the system. To test it out first, you can remove the last -y, and it will show you what it will purge without actually doing it. I mean it never hurts to check first, "just in case." ;)

s(){ sed 's/./\n\0/g'<<<$1|sort;};cmp -s <(s foobar) <(s farboo)||echo -n "not ";echo anagram
2011-02-17 12:42:45
User: flatcap
Functions: cmp echo sed
-3

Are the two strings anagrams of one another?

sed splits up the strings into one character per line

the result is sorted

cmp compares the results

Note: This is not pretty. I just wanted to see if I could do it in bash.

Note: It uses fewer characters than the perl version :-)

ls -alt /directory/ | awk '{ print $6 " " $7 " -- " $9 }'
tmpfs(){ cd /;for i in $@;do tar czvf /tmp/$i $i;mount -t tmpfs tmpfs /$i;tar xvzf /tmp/$i;cd ~ ;}# usage: tmpfs etc var
ps h -o pid,command | grep 'TEXT' | sed 's/^ \+//' | cut -d ' ' -f 1 | xargs -n 1 kill