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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!

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Maintained by Jon H.

Site originally by David Winterbottom (user root).

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 - 12,388 results
watch -n 1 cat /proc/net/wireless
2012-06-07 10:38:21
User: cantormath
Functions: cat watch

Values will depend on the driver and the hardware specifics, so you need to refer to your driver documentation for proper interpretation of those values.

perl -e 'use Date::Calc qw(Today Week_Number); $weekn = Week_Number(Today); print "$weekn\n"'
cd <YOUR_DIRECTORY>; for i in `ls ./`; do tar czvf "$i".tar.gz "$i" ; done
2009-06-11 18:33:27
User: ElAlecs
Functions: cd tar

Very simple and useful, you need to change the word "directory" for your directory

tar -zcvpf backup_`date +"%Y%m%d_%H%M%S"`.tar.gz `find <target> -atime +5 -type f` 2> /dev/null | parallel -X rm -f
2010-01-28 12:41:41
Functions: rm tar

This deals nicely with files having special characters in the file name (space ' or ").

Parallel is from https://savannah.nongnu.org/projects/parallel/

alias whatismyip="wget -q -O - http://whatismyip.com/automation/n09230945.asp"
2009-10-30 15:42:52
User: gibboris
Functions: alias

The preferred way for scripts (and easier to parse)

MyVAR=84; awk '{ print "'"$MyVAR"'" }'
tail /var/log/auth.log -n 100
UNIQUE_BY_MAC=$(ifconfig |grep eth0|awk '{ print strtonum("0x"substr($6,16,2)) }')
2010-06-01 17:34:43
User: rubo77
Functions: awk grep ifconfig

gets the last number of the mac address to use it for other stuff

screen -x `screen -ls | grep Detached | cut -c -10`
2012-03-01 14:13:09
User: peter4512
Functions: cut grep screen
Tags: gnu screen

I alias this as "tach":

alias tach='screen -x `screen -ls | grep Detached | cut -c -10`'

If you have several detached sessions it will just grab the first one. If you're running nested screens you can open new outer windows and run tach repeatedly to grab all the detached sessions into that one.

ips(){ for if in ${1:-$(ip link list|grep '^.: '|cut -d\ -f2|cut -d: -f1)};do cur=$(ifconfig $if|grep "inet addr"|sed 's/.*inet addr:\([0-9\.]*\).*/\1/g');printf '%-5s%-15s%-15s\n' $if $cur $(nc -s $cur sine.cluenet.org 128 2>/dev/null||echo $cur);done;}
2009-08-07 10:04:46
User: frozenfire
Functions: cut echo grep ifconfig link sed

Gets the internal and external IP addresses of all your interfaces, or the ones given as arguments

curl --basic --user username:password --data status="Twitter from commandline with curl" https://twitter.com/statuses/update.xml
2010-07-06 05:25:51
User: emacs

--basic --user username:password

This will authenticate your Twitter username and password

--data status=""

Send data to the API with POST HTTP form.

lsof | grep 'DEL.*lib' | cut -f 1 -d ' ' | sort -u
2011-05-30 20:45:58
User: leenucks
Functions: cut grep sort

Useful after a complete system update (without a new kernel) when you want to know, which processes need to be restarted

dd if=/dev/zero of=/fs/to/fill/dummy00 bs=8192 count=$(df --block-size=8192 / | awk 'NR!=1 {print $4-100}')
2009-12-03 15:20:18
User: arcege
Functions: awk dd df
Tags: dd df

For disk space constraint testing. Leaves a little space available for creating temp files, etc. Easily free up the used disk space again by deleting the dummy00 file. Can tailor the testing by building smaller 'blocks' to suit the needs of the testing.

WARNING: do not do this to the '/' (root) filesystem unless you know what you are doing... on some systems it could crash the OS.

chmod -R u=rwX,go=rX .
alias ':q'='exit'; alias ':e'='vim';
2012-08-12 12:35:10
User: expelledboy
Functions: alias
Tags: vim alias

This was me just succumbing to the habits, but now I rarely use quit or vim directly, so beware! :)

2009-07-16 08:07:35
User: Blackbit

I don't know why this ain't written as simply as it is. I always see it's just used as parameter, like: vi `!!`

But i use it to repeat a command, as i always work on several shells and check the result of one shell on a second.

response.headers['Cache-Control'] = 'public, max-age=60';
2011-07-11 23:35:36
User: evandrix

possible options:

* Varnish

* Squid in reverse proxy mode

* Django's cache framework

* rack-cache

* or CDN, like Akamai

(Command too long..See sample Output..)
2009-06-14 20:34:37
User: mohan43u
Tags: bash sed echo tr od

curl doesn't provide url-encoding for 'GET' data, it have an option '--data-urlencode', but its only for 'POST' data. Thats why I need to write down this commandline. With 'perl', 'php' and 'python', this is one liner, but just I wrote it for fun. Works in Ubuntu, will work in all linux varients(I hope it will work in unix varients also).

ssh-copy-id [-i [identity_file]] [user@]machine
for i in ./*.$1; do mv "$i" `echo $i | tr ' ' '_'`; done for i in ./*.$1; do mv "$i" `echo $i | tr '[A-Z]' '[a-z]'`; done for i in ./*.$1; do mv "$i" `echo $i | tr '-' '_'`; done for i in ./*.$1; do mv "$i" `echo $i | tr -s '_' `; done
export PATH=$PATH:`pwd`
2011-02-05 06:29:54
User: YogiBare
Functions: export

This will temporarily add the current directory to your $PATH. Allowing you to execute from that directory for the duration of the session.

tar cvf - /src | ( cd /dest ; tar xvf - )
2011-09-22 15:35:24
User: a8ksh4
Functions: cd tar

This is how I've done it in the past

echo -e "aa\nbb\ncc\ndd\n123" | sed -e :a -e "/$/N; s/\n/;/; ta"
ps ho command $$
echo $SHELL