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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.




Commands by camocrazed from sorted by
Terminal - Commands by camocrazed - 9 results
chvt 7 ; sleep 2 ; DISPLAY=:0.0 import -window root screenshot.png
2010-08-20 17:28:49
User: camocrazed
Functions: chvt sleep

when using Gnome or KDE, you will have a hard time getting a screenshot of something like a login screen, or any other screen that occurs before the desktop environment is up and monitoring the printscreen key. (this probably applies for other DEs as well, but I haven't used them)

What this command is meant to do is take a screenshot of an X window using a command you can run from your virtual terminals (actual text terminals, not just an emulator) To do this:

Press CTRL+ALT+F1 to go to a virtual (text) terminal once your login window comes up

Login to the virtual terminal and enter the command (you'll have to type it in)

You should now have a file called screenshot.png in your home directory with your screenshot in it.

For those of you who are new to the virtual terminal thing, you can use CTRL+ALT+F7 to get back to your regular GUI

From http://www.gnome.org

dir="/bin"; man $(ls $dir |sed -n "$(echo $(( $RANDOM % $(ls $dir |wc -l | awk "{ print $1; }" ) + 1 )) )p")
2010-08-20 16:31:50
User: camocrazed
Functions: dir ls man sed
Tags: man sed awk echo wc

Broaden your knowledge of the utilities available to you in no particular order whatsoever! Then use that knowledge to create more nifty one-liners that you can post here. =p

Takes a random number modulo the number of files in $dir, prints the filename corresponding to that number, and passes it as an argument to man.

sox Klaxon.mp3 -t wav - |ssh thelab@company.com paplay
2010-07-29 23:23:39
User: camocrazed
Functions: ssh

This will allow you to convert an audio file to wav format, and send it via ssh to a player on the other computer, which will open and play it there. Of course, substitute your information for the sound file and remote address

You do not have to use paplay on the remote end, as it is a PulseAudio thing. If the remote end uses ALSA, you should use aplay instead. If it uses OSS, you should berate them about having a lousy sound system. Also, you're not limited to transmitting encoded as wav either, it's just that AFAIK, most systems don't come with mp3 codecs, but will play wav files fine.

If you know SoX is installed on the remote end and has mp3 codecs, you can use the following instead:

cat Klaxon.mp3 |ssh thelab@company.com play -t mp3 -

this will transmit as mp3. Again, use your specific information. if you're not playing mp3s, use another type with the -t option

for file in $(ls /usr/bin ) ; do man -w $file 2>> nomanlist.txt >/dev/null ; done
2010-07-26 19:39:53
User: camocrazed
Functions: file ls man
Tags: man

This takes quite a while on my system. You may want to test it out with /bin first, or background it and keep working.

If you want to get rid of the "No manual entry for [whatever]" and just have the [whatever], use the following sed command after this one finishes.

sed -n 's/^No manual entry for \(.*\)/\1/p' nomanlist.txt
tee >(cat - >&2)
2010-07-20 17:22:31
User: camocrazed
Functions: cat tee

the tee command does fine with file names, but not so much with file descriptors, such as &2 (stderr). This uses process redirection to tee to the specified descriptor.

In the sample output, it's being used to tee to stderr, which is connected with the terminal, and to wc -l, which is also outputting to the terminal. The result is the output of bash --version followed by the linecount

echo -n "text" | od -A n -t x1 |sed 's/ /\\x/g'
2010-07-14 15:31:36
User: camocrazed
Functions: echo od sed
Tags: sed hex ascii od

If you're going to use od, here's how to suppress the labels at the beginning. Also, it doesn't output the \x, hence the sed command at the end. Remove it for space separated hex values instead

printf $(( echo "obase=16;$(echo $$$(date +%s%N))"|bc; ip link show|sed -n '/eth/ {N; p}'|grep -o -E '([[:xdigit:]]{1,2}:){5}[[:xdigit:]]{1,2}'|head -c 17 )|tr -d [:space:][:punct:] |sed 's/[[:xdigit:]]\{2\}/\\x&/g')|sha1sum|head -c 32; echo
2010-07-14 14:04:53
User: camocrazed
Functions: echo grep head link printf sed tr
Tags: uuid

first off, if you just want a random UUID, here's the actual command to use:


Your chances of finding a duplicate after running this nonstop for a year are about the same as being hit by a meteorite before finishing this sentence

The reason for the command I have is that it's more provably unique than the one that uuidgen creates. uuidgen creates a random one by default, or an unencrypted one based on time and network address if you give it the -t option.

Mine uses the mac address of the ethernet interface, the process id of the caller, and the system time down to nanosecond resolution, which is provably unique over all computers past, present, and future, subject to collisions in the cryptographic hash used, and the uniqueness of your mac address.

Warning: feel free to experiment, but be warned that the stdin of the hash is binary data at that point, which may mess up your terminal if you don't pipe it into something. If it does mess up though, just type

expand -t 2 <filename>
2010-07-13 23:04:57
User: camocrazed
Functions: expand
Tags: expand

Change the number to change the number of spaces. Leaving it out defaults to 8. Leaving out the filename defaults to stdin.

And to do it in reverse, you can use the unexpand command.

echo -n 'text' | xxd -ps | sed 's/[[:xdigit:]]\{2\}/\\x&/g'
2010-07-13 21:46:30
User: camocrazed
Functions: echo sed
Tags: sed hex ascii

Same as another one I saw, just with a cleaner sed command

Edit: updated the sed command to use the [[:xdigit:]] character class - more portable between locales

Note that it will have a newline inserted after every 32 characters of input, due to the output of xxd