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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!

Top Tags



Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

All commands from sorted by
Terminal - All commands - 12,380 results
watch -n 1 nc localhost 80 '<<EOF GET / HTTP/1.1 Host: tux-ninja Connection: Close EOF'
2009-08-06 23:20:31
User: JustinHop
Functions: watch

Use the command watch, which is really hard to pass nested quotes to, and insert newlines where they are supposed to go in the HTTP request. that is after 1.1 after the host and two newlines at the end before the EOF.

i use this all day

what? no support for HEREDOCs on commandlinefu's interface? need more fu.

cat files.txt | xargs tar -cv | tar -x -c $DIR/
2009-08-06 22:55:21
User: lingo
Functions: cat tar xargs

If you want certain files out of a directory hierarchy, this will copy just the listed files, but will create the directory hierarchy in the new location ($DIR/)

ifconfig $devices | grep "inet addr" | sed 's/.*inet addr:\([0-9\.]*\).*/\1/g'
rm -d **/*(/^F)
2009-08-06 21:41:19
User: claytron
Functions: rm
Tags: find zsh glob

This command uses the recursive glob and glob qualifiers from zsh. This will remove all the empty directories from the current directory down.

The **/* recurses down through all the files and directories

The glob qualifiers are added into the parenthesis. The / means only directories. The F means 'full' directories, and the ^ reverses that to mean non-full directories. For more info on these qualifiers see the zsh docs: http://zsh.dotsrc.org/Doc/Release/Expansion.html#SEC87

find . -name "-help" -exec mv {} help.txt \;
sudo snmptrap -m ALL -v 2c -c public trapserver "" UCD-DEMO-MIB::ucdDemoPublic SNMPv2-MIB::sysLocation.0 s "Just here"
cp path/filename{,-$(date +%Y-%m-%d)}
2009-08-06 13:50:00
User: vutcovici
Functions: cp date

It will create a backup of the filename. The advantage is that if you list the folder the backups will be sorted by date. The command works on any unix in bash.

wget -O - http://checkip.dyndns.org|sed 's/[^0-9.]//g'
fetch -q -o - http://ipchicken.com | egrep -o '([[:digit:]]{1,3}\.){3}[[:digit:]]{1,3}'
2009-08-06 11:57:44
User: spackle
Functions: egrep

Same thing as above, just uses fetch and ipchicken.com

nmap -PN -d -p445 --script=smb-check-vulns --script-args=safe=1 IP-RANGES
curl -s 'http://checkip.dyndns.org' | sed 's/.*Current IP Address: \([0-9\.]*\).*/\1/g'
html2text http://checkip.dyndns.org | grep -i 'Current IP Address:'|cut -d' ' -f4
2009-08-06 11:30:32
User: adonis28850
Functions: cut grep

The same as the other user, but smarter, using -d and -f

ulimit -s 64
2009-08-06 10:40:25
User: ioggstream
Functions: ulimit
Tags: Linux ulimit

default stack size is 10M. This makes your multithread app filling rapidly your memory.

on my PC I was able to create only 300thread with default stack size.

Lower the default stack size to the one effectively used by your threads, let you create more.

ex. putting 64k I was able to create more than 10.000threads.

Obviously ...your thread shouldn't need more than 64k ram!!!

ldapmodify -Y "dn:uid=rob,dc=example.com" -g -R -J 2.16.840.1.113730.3.4.16 ...
html2text http://checkip.dyndns.org | grep -i 'Current IP Address:'|cut -c21-36
curl -u yourusername:yourpassword -d status=?Your Message Here? https://twitter.com/statuses/update.xml
schedtool 1
2009-08-06 08:42:03

Display information about the cores.

* sudo apt-get install schedtool

mencoder "mf://frame_*.bmp" -mf w=720:h=480:fps=30:type=bmp -ovc lavc -lavcopts vcodec=mpeg4 -o number_video.mp4
2009-08-06 06:59:49

Converts the batch of images to video.

*mencoder* required.

sudo cat /usr/share/icons/*/*/* > /dev/dsp
2009-08-06 03:12:27
User: 12345678
Functions: cat sudo

Plays the sound of the file, should sound like *some* kind of music, most files sound like static but some are really cool.


sudo cat /dev/sda > /dev/dsp sudo cat /dev/sda5 | aplay

Check out http://bbs.archlinux.org/viewtopic.php?id=70937 for more variations!

semi-dupe--like http://www.commandlinefu.com/commands/view/985/generate-white-noise but with different syntax and program.

sed "s:/old/direcory/:/new/directory/:" <file>
2009-08-06 00:37:45
Functions: sed
Tags: sed

Having to escape forwardslashes when using sed can be a pain. However, it's possible to instead of using / as the separator to use : .

I found this by trying to substitute $PWD into my pattern, like so

sed "s/~.*/$PWD/" file.txt

Of course, $PWD will expand to a character string that begins with a / , which will make sed spit out an error such as "sed: -e expression #1, char 8: unknown option to `s'".

So simply changing it to

sed "s:~.*:$PWD:" file.txt

did the trick.

find . -type f -print0 | xargs -0 -P 4 -n 40 grep -i foobar
2009-08-05 23:18:44
User: ketil
Functions: find grep xargs

xargs -P N spawns up to N worker processes. -n 40 means each grep command gets up to 40 file names each on the command line.

echo "Body goes here" | mutt -s "A subject" -a /path/to/file.tar.gz [email protected]
2009-08-05 23:06:25
User: ketil
Functions: echo

This command uses mutt to send the mail. You must pipe in a body, otherwise mutt will prompt you for some stuff. If you don't have mutt, it should be dead easy to install.

make -j 4
2009-08-05 22:50:57
User: kovan
Functions: make

Force make command to create as many compile processes as specified (4 in the example), so that each one goes into one core or CPU and compilation happens in parallel. This reduces the time required to compile a program by up to a half in the case of CPUs with 2 cores, one fourth in the case of quad cores... and so on.

colormake, colorgcc, colordiff
2009-08-05 22:40:11
User: kovan

Colorize output of make, gcc/g++ or diff, making it easier to read at a glance.

They are not distributed with make, diff or gcc, but are usually available in the repositories.