Hide

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again.

Delete that bloated snippets file you've been using and share your personal repository with the world. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.


Get involved!

You can sign-in using OpenID credentials, or register a traditional username and password.

First-time OpenID users will be automatically assigned a username which can be changed after signing in.

Universal configuration monitoring and system of record for IT.
Hide

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for:

Hide

News

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!
Hide

Top Tags

Hide

Functions

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 - 12,372 results
xdg-open .
2009-09-09 07:20:32
User: karpoke
Tags: xdg-open
2

Opens a file or URL in the user's preferred application.

echo -e "${PATH//://\n}" >/tmp/allpath; grep -Fh -f /tmp/allpath /var/lib/dpkg/info/*.list|grep -vxh -f /tmp/allpath >/tmp/installedinpath ; find ${PATH//:/ } |grep -Fxv -f /tmp/installedinpath
2009-09-09 05:33:14
User: kamathln
Functions: echo find grep
Tags: Debian dpkg PATH
0

OS: Debian based (or those that use dpkg)

Equivalent to doing a dpkg -S on each file in $PATH, but way faster.

May report files generated though postinstall scripts and such. For example . It will report /usr/bin/vim .. which is not not a file installed directly by dpkg, but a link generated by alternatives hooks

gnome-open .
ssh root@`for ((i=100; i<=110; i++));do arp -a 192.168.1.$i; done | grep 00:35:cf:56:b2:2g | awk '{print $2}' | sed -e 's/(//' -e 's/)//'`
2009-09-09 04:32:20
User: gean01
Functions: arp awk grep sed ssh
8

Connect to a machine running ssh using mac address by using the "arp" command

echo src::${PATH} | awk 'BEGIN{pwd=ENVIRON["PWD"];RS=":";FS="\n"}!$1{$1=pwd}$1!~/^\//{$1=pwd"/"$1}{print $1}'
2009-09-09 04:03:46
User: arcege
Functions: awk echo
Tags: awk echo PATH
-2

Removes trailing newline; colon becomes record separator and newline becomes field separator, only the first field is ever printed. Replaces empty entries with $PWD. Also prepend relative directories (like ".") with the current directory ($PWD). Can change PWD with env(1) to get tricky in (non-Bourne) scripts.

echo $PATH | tr \: \\n
2009-09-09 02:10:04
User: crk
Functions: echo tr
Tags: bash echo tr PATH
15

This version uses Pipes, but is easier for the common user to grasp... instead of using sed or some other more complicated method, it uses the tr command

nautilus `pwd`
zip -r foo.zip DIR -x "*/.svn/*"
find . -not \( -name .svn -prune \) -type f | xargs zip XXXXX.zip
diff <(openssl x509 -noout -modulus -in server.crt ) <( openssl rsa -noout -modulus -in server.key )
2009-09-08 12:08:34
User: ari
Functions: diff
3

A x509 certificate and a rsa key file have in common a parameter called modulus, it is a very long hexadecimal number.

That value is unique for each certficate / key pair.

The command allows to do the check of this pair of values in a script using a great feature of bash. "

find . -name \*.c | xargs wc -l | tail -1 | awk '{print $1}'
2009-09-08 08:25:45
User: karpoke
Functions: awk find tail wc xargs
Tags: awk find wc
0

This is really fast :)

time find . -name \*.c | xargs wc -l | tail -1 | awk '{print $1}'

204753

real 0m0.191s

user 0m0.068s

sys 0m0.116s

cdrdao read-cd --device ATA:1,1,0 --driver generic-mmc-raw --read-raw image.toc
ls -ldct /lost+found |awk '{print $6, $7}'
some_very_long_and_complex_command # label
2009-09-08 05:58:27
User: jamolkhon
89

When using reverse-i-search you have to type some part of the command that you want to retrieve. However, if the command is very complex it might be difficult to recall the parts that will uniquely identify this command. Using the above trick it's possible to label your commands and access them easily by pressing ^R and typing the label (should be short and descriptive).

UPDATE:

One might suggest using aliases. But in that case it would be difficult to change some parts of the command (such as options, file/directory names, etc).

file -i <textfile>
2009-09-08 01:33:19
User: juvenn
Functions: file
2

This command gives you the charset of a text file, which would be handy if you have no idea of the encoding.

curl -u username:password --silent "https://mail.google.com/mail/feed/atom" | tr -d '\n' | awk -F '<entry>' '{for (i=2; i<=NF; i++) {print $i}}' | sed -n "s/<title>\(.*\)<\/title.*name>\(.*\)<\/name>.*/\2 - \1/p"
2009-09-07 21:56:40
User: postrational
Functions: awk sed tr
44

Checks the Gmail ATOM feed for your account, parses it and outputs a list of unread messages.

For some reason sed gets stuck on OS X, so here's a Perl version for the Mac:

curl -u username:password --silent "https://mail.google.com/mail/feed/atom" | tr -d '\n' | awk -F '<entry>' '{for (i=2; i<=NF; i++) {print $i}}' | perl -pe 's/^<title>(.*)<\/title>.*<name>(.*)<\/name>.*$/$2 - $1/'

If you want to see the name of the last person, who added a message to the conversation, change the greediness of the operators like this:

curl -u username:password --silent "https://mail.google.com/mail/feed/atom" | tr -d '\n' | awk -F '<entry>' '{for (i=2; i<=NF; i++) {print $i}}' | perl -pe 's/^<title>(.*)<\/title>.*?<name>(.*?)<\/name>.*$/$2 - $1/'
cat testfile | hexdump -C
tar czf /path/archive_of_foo.`date -I`.tgz /path/foo
2009-09-07 05:45:33
Functions: tar
Tags: backup tar
1

creates a compressed tar archive of files in /path/foo and writes to a timestamped filename in /path.

tar --create --file /path/$HOSTNAME-my_name_file-$(date -I).tar.gz --atime-preserve -p -P --same-owner -z /path/
2009-09-07 04:52:12
User: Odin_sv
Functions: date tar
Tags: backup tar
1

Use tar command for a backup info with a date of creation

psg() { ps aux | grep "[${1[1]}]${1[2,-1]}"; }
2009-09-07 04:37:11
User: jedahan
Functions: grep ps
-5

alias ps?='psg' for maximum hawtness. Works in bash or zsh.

fuser -k `who -u | awk '$6 == "old" { print "/dev/"$2'}`
2009-09-07 03:36:43
User: lbonanomi
Functions: awk fuser
Tags: Linux solaris
2

Shell timeout variables (TMOUT) can be very liberal about what is classified as 'activity', like having an editor open. This command string will terminate the login shell for an user with more than a day's idle time.

pkg search SEARCH_TERM | awk '{print $NF}' | sed -e 's;.*/\(.*\)\@.*;\1;' | sort -u
system_profiler SPApplicationsDataType | perl -nl -e [email protected]=<>; [email protected]; while($j<$c){ $apps[$i].=$al[$j]; $i++ if ($al[$j] ) =~ /^\s\s\s\s\S.*:$/; $j++} while($k<$i){ $_=$apps[$k++]; if (/Kind: PowerPC/s) {print;}}'
2009-09-06 20:56:48
User: drewk
Functions: perl
Tags: Os X perl
0

This finds all the PowerPC apps recognized by OS X.

A better version is:

system_profiler SPApplicationsDataType 2> /dev/null | perl -

wnl -e '$i=$j=$k=$p=0; @al=; [email protected]; while($j

s[$i].=$al[$j]; $i++ if ($al[$j]) =~ /^\s\s\s\s\S.*:$/; $j++} while($k

apps[$k++]; if (/Kind: PowerPC/s) {print; $p++;}} print "$i applications, $p P

owerPC applications\n\n"'

but that is more than 255 characters...

find . -name '*.html' -exec 'sed' 's/.*class="\([^"]*\?\)".*/\1/ip;d' '{}' ';' |sort -su
2009-09-06 18:43:18
User: kamathln
Functions: find sort
1

Lists out all classes used in all *.html files in the currect directory. usefull for checking if you have left out any style definitions, or accidentally given a different name than you intended. ( I have an ugly habit of accidentally substituting camelCase instead of using under_scores: i would name soemthing counterBox instead of counter_box)

WARNING: assumes you give classnames in between double quotes, and that you apply only one class per element.

find . -regex '.*\(h\|cpp\)'
2009-09-06 11:33:19
User: Vereb
Functions: find
Tags: bash find
7

This is the way how you can find header and cpp files in the same time.