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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 - 12,363 results
2009-02-17 01:23:39
User: roliver

Files saved on a windows machine use different ascii characters for lines turns. When viewing such files in VI the will most often have a ^M(control-VM) character at the end of each line. This command will remove all occurrences of that character

man emacs
2011-08-17 00:37:00
User: cwimmer
Functions: man

Emacs backs up previous versions by default.

echo $[RANDOM % 100] # range 0-99
2013-05-25 19:02:00
User: anapsix
Functions: echo

use it to stagger cronjob or to get a random number

increase the range by replacing 100 with your own max value

i="0"; while [ $i -lt 5 ] ; do xpenguins & i=$[$i+1] ; done
2009-12-27 21:05:33
User: eastwind

just replace the number 5 with the variable you want , and the xpenguins software with the one you want

echo -n "String to MD5" | md5sum | cut -f1 -d' '
2011-03-05 03:53:09
User: xakon
Functions: cut echo md5sum

Nothing special about hashing here, only the use of cut, I think, could result at fewer keystrokes.

ls -ltr |grep 'May 12'|awk '{print $9;}'|xargs rm -v
find -iname '*.flac' | sed 's:/[^/]*$::' | uniq
2009-03-24 13:26:31
User: ar
Functions: find sed

Run this in your music folder, or give the path directly after "find".

The sed pattern filters away the basename.

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

dd if=/dev/zero of=filename.file bs=1024 count=10240
2012-01-19 08:38:14
User: harpo
Functions: dd

Command to create a dummy file (full of nulls). Useful for testing e.g. file transfers when no file is at hand.

bs = blocksize, count = filesize in kilobytes

unrar x *.rar
2010-12-08 21:50:23
User: yababay

unrar e ... extracts all files into current directory, without archived subdirectories order. unrar x is more accurate command.

rsync -a -v --delete sending_directory target_directory
/usr/ucb/ps -auxgww
2009-12-28 12:36:04
User: sharfah

Depending on your installation, when you run ps you will only get the first 40 or so characters displayed. In order to view the entire string, use /usr/ucb/ps on Solaris.

echo `lcg-infosites --vo lhcb ce | cut -f 1| grep [[:digit:]]| tr '\n' '+' |sed -e 's/\ //g' -e 's/+$//'`|bc -l
2010-11-10 15:06:00
User: kbat
Functions: bc cut echo grep sed tr

Of course, this command must be executed at a GRID User Interface

lhcb - name of your VO, substitute it with the one you are interested it.

netstat -t -p --extend | grep USERNAME
2012-08-07 02:25:54
User: wr8cr8
Functions: grep netstat

This obtains a list of open connections that a user is connected to if he/she is using a SSH tunnel

find /path/ -type f -exec grep -l '<string of text>' {} \; | xargs sed -i -e 's%<string of text>%<new text string>%g'
gominify() { if [ $# -ne 2 ]; then echo 'gominify < src > < dst >'; return; fi; s="$1"; d="$2"; java -jar yui.jar $s >$d; if [ $? == 0 ]; then a=$( ls -sh $s | awk '{print $1}' ); b=$( ls -sh $d | awk '{print $1}' ); echo "Saved $s ($a) to $d ($b)"; fi;}
2010-08-03 10:19:24
User: meathive
Functions: awk echo ls

This command, or a derivative like it, is a must-have if you're a server administrator interested in website optimization: https://kinqpinz.info/?%C2%B6=287a7ba6

Command requires Yahoo's YUI, find it here: http://developer.yahoo.com/yui/

find . -mtime +30 -exec mv {} old/ \;
2014-02-09 23:05:41
User: minnmass
Functions: find mv
Tags: bash file

Use find's built-in "exec" option to avoid having to do any weirdness with quoting.

find -name pom.xml | while read f; do cd $(dirname "$f"); mvn clean; cd -; done;
2015-04-15 21:24:49
User: glaudiston
Functions: cd dirname find read

this command is used to locate all pom.xml files, access the dir and do a mvn clean, but I do recommend you to disable network interfaces to not download dependencies packages to be faster.

while [ 1 ]; do date; ls -l /path/to/dir; sleep 1; done
tar -tf <file.tar.gz> | parallel rm
2010-01-28 08:28:16
Functions: tar

xargs deals badly with special characters (such as space, ' and "). To see the problem try this:

touch important_file

touch 'not important_file'

ls not* | xargs rm

Parallel https://savannah.nongnu.org/projects/parallel/ does not have this problem.

rename -n "s/-.*//" *
2011-03-06 12:08:39
User: pepin
Functions: rename

of course, replace the "-" after / by the character you wish. a dot must by protected by a backslash, as it is a regexp. it's the same result as the command proposed. but if there is more than a dash in the name, only the part before the first dash is kept... so that's not an "extension renaming" command.

echo 1 2 3 > FILE; while read -a line; do echo ${line[2]}; done < FILE
2009-03-06 15:32:40
User: occam
Functions: echo read
Tags: bash

This will print out the third column of every line in FILE. Useful for many files in /proc or *csv data.

ip link
tr -dc 'a-zA-Z0-9' < /dev/urandom | fold -w 10 | sed 1q
kill `ps aux | grep xmms | grep -v grep | awk '{ print $2 }'`
2010-11-11 17:26:26
User: corp769
Functions: awk grep kill

I use this command, within a cron job, to kill XMMS after a certain amount of time. This command returns the PID used by XMMS, and gets passed to the kill command. Another alternative would be ps aux | grep xmms | grep -v grep | awk '{ print $2 }' | xargs kill