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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/
2011-01-04 - Moderation now required for new commands
To try and put and end to the spamming, new commands require moderation before they will appear on the site.
2010-12-27 - Apologies for not banning the trolls sooner
Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.




All commands from sorted by
Terminal - All commands - 11,492 results
snmpwalk -v3 -On -u <user> -l NoAuthNoPriv -m ALL <HOST_IP> .
snmpwalk -v2c -c <community> -m ALL <HOST_IP> .
seq 100 | awk '{sum+=$1} END {print sum}'
2009-03-24 20:30:40
User: kaan
Functions: awk seq
Tags: awk seq

"seq 100" outputs 1,2,..,100, separated by newlines. awk adds them up and displays the sum.

"seq 1 2 11" outputs 1,3,..,11.


1+3+...+(2n-1) = n^2

seq 1 2 19 | awk '{sum+=$1} END {print sum}' # displays 100

1/2 + 1/4 + ... = 1

seq 10 | awk '{sum+=1/(2**$1)} END {print sum}' # displays 0.999023
alias tproxy='ssh -ND 8118 user@server&; export LD_PRELOAD="/usr/lib/libtsocks.so"'
alias myip='curl -s www.wieistmeineip.de | egrep -o "[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}"'
sed 's/\b\(0*\)//g' filename
2009-03-24 20:19:42
User: alperyilmaz
Functions: sed
Tags: sed

Leading zeros might help correct sorting and they can be removed by sed after sorting

sed -e :a -e 's/\(.*[0-9]\)\([0-9]\{3\}\)/\1,\2/;ta' filename
2009-03-24 20:06:02
User: alperyilmaz
Functions: sed
Tags: sed

Does not necessarily require a file to process, it can be used in a pipe as well:

cat filename | sed -e :a -e 's/\(.*[0-9]\)\([0-9]\{3\}\)/\1,\2/;ta'

I don't remember where I copy/pasted this from, I wish I credited the original author

head -c $((<pw-lenght>-2)) /dev/urandom | uuencode -m - | sed -e '1d' -e '3d' | sed -e 's/=.*$//g'
2009-03-24 20:05:16
User: P17
Functions: head sed uuencode

Replace < pw-length > with the desired password-length.

The password-length is not always correct, but wayne...

watch ethtool eth0
2009-03-24 20:03:25
User: israel
Functions: watch

verifry if link detected or no and speed of network.

mysql DATABASE -N -s -r -e 'SQL COMMAND'
2009-03-24 19:53:46
User: alperyilmaz
Tags: mysql

-N removes header

-s removes separator chars

-r raw output

After using these options, the MySQL ouptut can be used with pipes very easily

ps ax | grep <processname> | grep -v grep | awk '{print $1}' | sudo xargs kill -9
php -r 'echo strtotime("2009/02/13 15:31:30")."\n";'
2009-03-24 19:38:46
User: sudopeople

Most people know that you can run a PHP script from the command line like so:

php ./my_script.php

But sometimes I just want to run a quick bit of code, the PHP Command Line Interface allows me to do so with the -r option.

Requires package php5-cli

rpm -Va | grep -v "\.\.\.\.\.\.\.T"
cat -v -t -e
2009-03-24 19:29:03
User: alperyilmaz
Functions: cat
Tags: cat

Useful to detect number of tabs in an empty line, DOS newline (carriage return + newline).

A tool that can help you understand why your parsing is not working.

man -t man | lp
2009-03-24 19:08:07
User: icco
Functions: man
Tags: printing

man -t manpagename gives a postscript version of said man page. You then pipe it to ls, and assuming you have cups set up, it prints in your default printer.

echo -e "[client]\nuser = YOURUSERNAME\npassword = YOURPASSWORD" > ~/.my.cnf
2009-03-24 19:05:39
User: alperyilmaz
Functions: echo
Tags: mysql bash

The file .my.cnf located at user's home directory is used for mysql login. If this file exists, then


can be replaced with

mysql database -e 'SOME SQL COMMAND'

It saves you from typing!

This is valid for mysqladmin and mysqldump commands as well.

/usr/sbin/arp -i eth0 | awk '{print $3}' | sed 1d
date -d "@$(find dir -type f -printf '%C@\n' | sort -n | sed -n "$(($(find dir -type f | wc -l)/2))p")" +%F
2009-03-24 18:48:49
User: allengarvin
Functions: date dir find wc

I needed to get a feel for how "old" different websites were, based on their directories.

vimdiff foo.c <(bzr cat -r revno:-2 foo.c)
gs -q -sPAPERSIZE=a4 -dNOPAUSE -dBATCH -sDEVICE=pdfwrite -sOutputFile=test.pdf multipageproject.pdf
2009-03-24 17:14:46
User: iain
Functions: gs

Xsane produces PDFs that are too large - particularly multipage PDFs. This command compresses them. If you do not use A4, remove the -sPAPERSIZE flag.

tar -czf - * | ssh example.com "cat > files.tar.gz"
2009-03-24 17:02:02
User: migurski
Functions: ssh tar

I recently found myself with a filesystem I couldn't write to and a bunch of files I had to get the hell out of dodge, preferably not one at a time. This command makes it possible to pack a bunch of files into a single archive and write it to a remote server.

host google.com
2009-03-24 16:25:12
User: tommaso
Functions: host

host is a simple utility for performing DNS lookups. It is normally used to convert names to IP addresses and vice versa. When no arguments or options are given, host prints a short summary of its command line arguments and options.

2009-03-24 16:19:12
User: haivu
Functions: bc

bc is a wonderful calculator. Just type bc at the command line and have at it. Ctrl+D (or type quit) will get you out. This usage is just scratching the surface: bc can handle a mini scripting language, complete with variable, statements, loop, conditional statements and more. Do a man page on it to find out.

2009-03-24 16:03:28
User: haivu

Short and sweet command. This command is also useful for other information such as what IP address a particular user logged in from, how long had they been logged in, what shell do they use.

find . -regex "[^.]*" -depth -empty -type d -mtime +1 -exec rmdir -v {} \;