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.

If you have a new feature suggestion or find a bug, please get in touch via http://commandlinefu.uservoice.com/

Get involved!

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

OpenID
or
Sign in Register

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

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

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.
Hide

Tags

Hide

Functions

Hide

Credits

Site by David Winterbottom (user root).

Commands using cat

Commands using cat from sorted by
Terminal - Commands using cat - 380 results
cat `ls -r /sys/class/net/*/address` | sort -u
2011-06-02 23:16:37
User: jaimerosario
Functions: cat sort
Tags: sort mac
-2
Up
Down
List your MACs address
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cd /usr/share/gnome-shell/search_providers/ && cat google.xml | sed "s/www.google.com\/search/duckduckgo.com\//; s/Google/DuckDuckGo/g" > duckduckgo.xml
2011-05-27 22:07:36
User: scripteles
Functions: cat cd sed
0
Up
Down
Add DuckDuckGo Search as search provider on gnome-shell

Add DuckDuckGo Search as search provider on gnome-shell/gnome3 .

Needs root permission. To see the results, use alt+f2 and then type r.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat /dev/hda|netcat -q 0 192.168.1.2 9100
2011-05-22 05:03:28
User: robosquid
Functions: cat
0
Up
Down
Print out your hard drive to a jet-direct compatible printer.

Where 192.168.1.2 is a printer with jet-direct.

No, I don't suggest this as a backup method.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat /proc/mounts | awk '{print $2}' | grep "^$MOUNTPOINT" | sort -r | xargs umount
2011-05-17 05:54:42
User: boni
Functions: awk cat grep sort xargs
0
Up
Down
umount --rbind mount with submounts

Original: https://bugzilla.redhat.com/show_bug.cgi?id=194342

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
mysqldump OLD_DB | cat <(echo "CREATE DATABASE NEW_DB; USE NEW_DB;") - | mysql
2011-05-16 20:42:01
User: michaelmior
Functions: cat echo
Tags: mysql bash mysqldump
2
Up
Down
Create a backup copy of a MySQL database on the same host

This should probably only be used for testing in a dev environment as it's not terribly efficient, but if you're doing something that might trash a DB and you still want the old data available, this works like a charm.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat /sys/class/net/eth0/address
2011-05-13 13:40:08
User: barto
Functions: cat
10
Up
Down
List your MACs address
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat search_items.txt | while read i; do surfraw google -browser=firefox $i; done
2011-05-12 09:27:08
User: bubo
Functions: cat read
-1
Up
Down
automate web search and open tabs in firefox

tired of opening tabs and fill in search forms by hand? just pipe the search terms you need into this surfraw loop. you can use any browser you have installed, but a graphical browser with a tabbed interface will come in handy. surfraw can be found here:

http://surfraw.alioth.debian.org

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
nohup cat /dev/ttyS0 | tee -a llamadas.db&
2011-05-05 15:47:27
User: fjrojast
Functions: cat nohup tee
0
Up
Down
Dump /dev/ttyS0 on background automatically from startup

Put this command on /etc/rc.local.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find . -type f -name '*.php' | xargs cat | sed -re ':top /\/\*.*\*\// { s/\/\*.*\*\///g ; t top }; /\/\*/ { N ; b top }' | awk '$0 !~ /^[\t[:space:]]*($|(\/\/)|(#))/' | wc -l
2011-05-05 06:12:34
User: andrehgw
Functions: awk cat find sed top wc xargs
0
Up
Down
How many lines in your PHP project without comments

An advanced possibility to count the lines of code like in #8394

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
grabtweets() { curl -s -o $GT_TMP twitter.com/$1 | cat $GT_TMP | grep entry-content | sed -e :loop -e 's/<[^>]*>//g;/</N;//bloop' | sed 's/^[ \t]*//'; }
2011-05-04 21:49:08
User: gl101
Functions: cat grep sed
-1
Up
Down
view someone's twitter stream from terminal
Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
pdftk inp1.pdf inp2.pdf inp3.pdf cat output out.pdf
2011-04-17 20:03:27
User: linuts
Functions: cat
5
Up
Down
Concating pdf files
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat username_lovedtracks.xspf |perl -pe "s/.*<title>(.*)<\/title><creator>(.*)<\/creator>.*/Song: \1 Artist: \2/gi"> titles
2011-04-07 09:02:11
User: dustylc
Functions: cat perl
0
Up
Down
Change your exported xml love list from last.fm, into Song: songname Artist: artistname

Change your exported xml love list from last.fm, into Song: songname Artist: artistname

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cls(){ printf "\33[2J";} or, if no printf, cat >cls;<ctrl-v><ctrl+[>[2J<enter><ctrl+d> cls(){ cat cls;}
2011-04-06 01:51:45
User: argv
Functions: cat printf
13
Up
Down
clear screen, keep prompt at eye-level (faster than clear(1), tput cl, etc.)

this leaves the cursor at the bottom of the terminal screen, where your eyes are.

ctrl-l moves it to the top, forcing you to look up.

Comments (11) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
while cat /proc/net/dev; do sleep 1; done | awk '/eth0/ {o1=n1; o2=n2; n1=$2; n2=$10; printf "in: %9.2f\t\tout: %9.2f\r", (n1-o1)/1024, (n2-o2)/1024}'
2011-03-26 02:52:14
User: quadcore
Functions: awk cat printf sleep
Tags: Network watch rate interface
1
Up
Down
Watch RX/TX rate of an interface in kb/s

A shorter version

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
quota -q $(cat /etc/passwd|cut -d ':' -f 1)
2011-03-20 15:35:42
User: Juluan
Functions: cat cut quota
5
Up
Down
Report all quota usage

Check disk quota for all user

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat /dev/zero | pv | ssh 192.168.1.2 "cat > /dev/null"
2011-03-20 09:31:52
User: shanx
Functions: cat ssh
5
Up
Down
Checks throughput between two nodes

This will show the throughput between two nodes.

Thanks to szboardstretcher, who posted it here: http://www.linuxquestions.org/questions/linux-networking-3/quick-and-easy-way-to-measure-throughput-between-two-nodes-868998/

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
function rot13 { if [ -r $1 ]; then cat $1 | tr '[N-ZA-Mn-za-m5-90-4]' '[A-Za-z0-9]'; else echo $* | tr '[N-ZA-Mn-za-m5-90-4]' '[A-Za-z0-9]'; fi }
2011-03-18 09:59:41
User: twjolson
Functions: cat echo tr
Tags: Linux unix tr
-5
Up
Down
ROT13 using the tr command

Will rot 13 whatever parameter follows 'rot13', whether it is a string or a file. Additionally, it will rot 5 each digit in a number

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat /backup/hd7/rdiff-log.txt |grep Processing | awk '{ print $4 }' | sed -e 's/\// /g' | awk '{ print $1 }' |uniq -c |sort -n
2011-03-12 18:49:09
User: kraja
Functions: awk cat grep sed sort uniq
Tags: rdiff rdiff-backup
1
Up
Down
most changed files in domains by rdiff-backup output
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ps ax > processes && cat processes | egrep "*.exe |*exe]" | awk '{ print $1 }' > pstokill && kill $(cat pstokill) && rm processes && rm pstokill
2011-02-26 16:13:58
User: sxiii
Functions: awk cat egrep kill ps rm
Tags: kill wine exe
-4
Up
Down
kill all running instances of wine and programs runned by it (exe)

This command kills all wine instances and each EXE application working on a PC.

Here is command info:

1) ps ax > processes = save process list to file named "processes" (we save it because we don't wont egrep to be found in the future)

2) cat processes | egrep "*.exe |*exe]" = shows the file "processes" and after greps for each *.exe and *exe] in it

3) | awk '{ print $1 }' > pstokill = saves processes PID's to file "pstokill" using awk filter

4) kill $(cat pstokill) = kills each PID in file pstokill, which is shown by cat program

5) rm processes && rm pstokill = removes temporary files

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
pdftk in.pdf cat 1S output out.pdf
2011-02-25 00:51:50
User: odoepner
Functions: cat
Tags: pdf pdftk
4
Up
Down
Rotate a single page PDF by 180 degrees

More pdftk examples: http://www.pdflabs.com/docs/pdftk-cli-examples/

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat file1 file2|awk -v RS='paragraph delimiter' '{print $0"\n"}'|sed -e '/./{H;$!d;}' -e 'x;/string to search/!d;'
2011-02-21 09:22:41
User: vitti
Functions: awk cat sed
0
Up
Down
print all paragraphs containing string

Concatenate file1 and file2, define paragraph, and search within each paragraph the ones containing the search string, and print just these paragraphs!

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat tarfile.tar.gz | ssh server.com " cd /tmp; tar xvzf - directory/i/want"
2011-02-11 17:10:01
User: alf
Functions: cat ssh
Tags: ssh tar
0
Up
Down
Untar a directory in a tar file over ssh

This may be listed already but this command is useful to untar a specific directory to a different server.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat LOCALFILE | ssh HOST "cat > REMOTEFILE"
2011-02-03 05:29:06
User: eataudio
Functions: cat ssh
Tags: uuencode uudecode file transfer
0
Up
Down
Copy a file over SSH without SCP

Nice command for when you don't have scp available for whatever reason.

Works with binaries.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat /dev/sda | pv -r > /dev/null
2011-01-23 22:58:56
User: kerim
Functions: cat
Tags: cat hard disk read harddisk pv speed hdparm hard drive disk
-1
Up
Down
Detect your computer's harddisk read speed without disk cache speed

Change your drive letter as you wish.

Using pv command for speed detect.First of all you must install pv command for usage.

http://www.bayner.com/

kerim@bayner.com

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat YOUR_FILE|tr -d '[:punct:]'|tr '[:upper:]' '[:lower:]'|tr -s ' ' '\n'|sort|uniq -c|sort -rn
2011-01-14 12:34:06
User: akap475a
Functions: cat sort tr uniq
1
Up
Down
Count the frequency of every word for a given file

Counts the frequency of words in a file

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate