All commands

All commands (14,187)

sorted by

Replaces every ocurrences of 'old' for 'new' in all files specified

Replaces every ocurrence of 'old' for 'new' in all files specified. After the 'i' char you can put a '~' or whatever to create a backup file for each replaced with the name equal to the original plus character.
This is sample output - yours may be different.
0

perl -i -pe "s/old/new/g" *

pandres · 2009-02-05 12:07:27 66
cycle through a 256 colour palette

just for fun
This is sample output - yours may be different.
14

yes "$(seq 232 255;seq 254 -1 233)" | while read i; do printf "\x1b[48;5;${i}m\n"; sleep .01; done

pixelbeat · 2009-02-05 12:01:37 25
Serve current directory tree at http://$HOSTNAME:8000/
This is sample output - yours may be different.
846

python -m SimpleHTTPServer

pixelbeat · 2009-02-05 11:57:43 146
Shows the largest files in your archives
This is sample output - yours may be different.
0

tar -tvjf backup.tar.bz2 | sort -nrk 3 | head

Sekenre · 2009-02-05 11:57:18 89
Remove invalid host keys from ~/.ssh/known_hosts

Useful if you have to tunnel ssh through a local port and it complains of the host key being different. Much easier than manually editing the file.
This is sample output - yours may be different.
9

ssh-keygen -R \[localhost\]:8022

Sekenre · 2009-02-05 11:48:09 113
find all processes named hunger and force kill, minus the grep itself and output to a file called fu.bar
This is sample output - yours may be different.
-3

ps -auwx|egrep hunger|grep -v grep| awk '{print "kill -9",$1}' > ~/fu.bar

lendellray · 2009-02-05 11:43:38 30
rgrep: recursive grep without .svn

Only excludes .svn from filenames. Show Sample Output
This is sample output - yours may be different.
```
[nf@dev ~/css]$ rgrep sprites
./template.php:require "css_sprites.php";
./template.php: $abs_path.'/sprites/',
./template.php: 'sprites.css',
./template.php:include 'sprites.css';
```
2

alias rgrep="find . $ ! -name .svn -o -prune $ -type f -print0 | xargs -0 grep"

nf · 2009-02-05 11:23:23 34
Get the 10 biggest files/folders for the current direcotry
This is sample output - yours may be different.
51

du -s * | sort -n | tail

bambambazooka · 2009-02-05 11:18:43 33
Start urxvt and do whatever is needed to open the screen session named "main"

Open a terminal (urxvt in this case) to connect to a screen session (named "main") and create the screen session if necessary.
This is sample output - yours may be different.
0

screen -ls | grep main && urxvt -name screen -e screen -x main || urxvt -name screen -e screen -R -S main

trey · 2009-02-05 10:51:31 191
SSH to a machine's internet address if it is not present on your local network

Ping machine once, waiting 1 second for response until failing. Upon fail, ssh globally, otherwise ssh locally.
This is sample output - yours may be different.
1

ping localip -c 1 -W 1 &> /dev/null && ssh localip || ssh globalip

trey · 2009-02-05 10:40:26 524
search the manual page names and descriptions
This is sample output - yours may be different.
2

apropos somekeyword

chrisdrew · 2009-02-05 10:29:15 57
locate bin, src, and man file for a command
This is sample output - yours may be different.
4

whereis somecommand

chrisdrew · 2009-02-05 10:29:10 745
locate a command

Returns the pathnames of the files which would be executed in the current environment had its arguments been given as a command.
This is sample output - yours may be different.
0

which somecommand

chrisdrew · 2009-02-05 10:29:04 41
Search through files, ignoring .svn

Variant of find grep that ignores files with .svn in the name. Useful for searching through a local repository of source code.
This is sample output - yours may be different.
-2

find . -type f -print0 | grep -vzZ '.svn' | xargs -0 grep --color -nEHi "SEARCHTERM"

troelskn · 2009-02-05 10:27:15 39
cd canonical (resolve any symlinks)
This is sample output - yours may be different.
-1

alias cdc='cd `pwd -P`'

adavies42 · 2009-02-05 10:15:11 36
ring the bell
This is sample output - yours may be different.
3

alias beep='echo -en "\007"'

adavies42 · 2009-02-05 10:14:24 33
get a directory from one machine to another using tar and ssh
This is sample output - yours may be different.
3

ssh somemachine "cd some dir; tar zcpf - somedirname" |tar zxpf -

mischamolhoek · 2009-02-05 09:10:56 30
A nice command for summarising repeated information
This is sample output - yours may be different.
4

alias counts=sort | uniq -c | sort -nr

porges · 2009-02-05 08:24:02 519
Rip audio from a video file.

Replace and accordingly.
This is sample output - yours may be different.
68

mplayer -ao pcm -vo null -vc dummy -dumpaudio -dumpfile <output-file> <input-file>

sykora · 2009-02-05 08:17:04 40
diff two unsorted files without creating temporary files

bash/ksh subshell redirection (as file descriptors) used as input to diff
This is sample output - yours may be different.
100

diff <(sort file1) <(sort file2)

systemj · 2009-02-04 22:20:13 502
Run a command only when load average is below a certain threshold

Good for one off jobs that you want to run at a quiet time. The default threshold is a load average of 0.8 but this can be set using atrun. Show Sample Output
This is sample output - yours may be different.
```
job 6 at 2009-02-04 19:03
```
45

echo "rm -rf /unwanted-but-large/folder" | batch

root · 2009-02-04 19:07:52 45
Get the full path to a file

Useful in scripts when the file is passed in as an argument. Eg. filepath=$(realpath $1) Show Sample Output
This is sample output - yours may be different.
```
/full/path/to/examplefile.txt
```
7

realpath examplefile.txt

root · 2009-02-04 15:41:44 46
Compare a remote file with a local file

Useful for checking if there are differences between local and remote files.
This is sample output - yours may be different.
176

ssh user@host cat /path/to/remotefile | diff /path/to/localfile -

root · 2009-02-04 11:33:19 79

Search gzipped files

This decompresses the file and sends the output to STDOUT so it can be grepped. A good one to put in loops for searching directories of gzipped files, such as man pages. Show Sample Output

-7

zcat /usr/share/man/man1/grep.1.gz | grep "color"

root · 2009-02-04 09:38:45 54

Display all readline binding that use CTRL

Useful for getting to know the available keyboard shortcuts. Show Sample Output

bind -p | grep -F "\C"

root · 2009-02-03 16:22:14 57

‹ First < 564 565 566 567 568 >

What's this?

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

Share Your Commands

Check These Out

Stream (almost) any music track in mplayer

Just give it an artist and/or song at the end of the command as shown.

Stat each file in a directory

Possible simplification of egrep-awk-sort with find and -exec with xargs.

Have netcat listening on your ports and use telnet to test connection

This will start a netcat process listening on port 666. If you are able connect to your your server, netcat will receive the data being sent and spit it out to the screen (it may look like random garbage, so you might want to redirect it to a file).

Change every instance of OLD to NEW in file FILE

Very quick way to change a word in a file. I use it all the time to change variable names in my PHP scripts (sed -i 's/$oldvar/$newvar/g' index.php)

Colorized grep in less

Get your colorized grep output in less(1). This involves two things: forcing grep to output colors even though it's not going to a terminal and telling less to handle those properly.

Execute a command on logout

Execute a command on shell logout,and run it until is finished,then shell is closed.

Create a bash script from last n commands

Uses history to get the last n+1 commands (since this command will appear as the most recent), then strips out the line number and this command using sed, and appends the commands to a file.

Determine if photos have been rotated to portrait orientation instead of normal landscape orientation

Most people take photos in landscape orientation (wider than it is tall). Sometimes though you turn the camera sideways to capture a narrow/tall subject. Assuming you then manually rotate those picture files 90 degrees for proper viewing on screen or photo frame, you now have a mix of orientations in your photos directory. This command will print out the names of all the photos in the current directory whose vertical resolution is larger than its horizontal resolution (i.e. portrait orientation). You can then take that list of files and deal with them however you need to, like re-rotating back to landscape for consistent printing with all the others. This command requires the "identify" command from the ImageMagick command-line image manipulation suite. Sample output from identify: $ identify PICT2821.JPG PICT2821.JPG JPEG 1536x2048 1536x2048+0+0 8-bit DirectClass 688KB 0.016u 0:00.006

Show numerical values for each of the 256 colors in bash

Same as http://www.commandlinefu.com/commands/view/5876, but for bash. This will show a numerical value for each of the 256 colors in bash. Everything in the command is a bash builtin, so it should run on any platform where bash is installed. Prints one color per line. If someone is interested in formatting the output, paste the alternative.

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

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:

» all commands
» commands with 3 up-votes (commandlinefu3)
» commands with 10 up-votes (commandlinefu10)

All commands (14,187) the last day the last week the last month all time sorted by date votes

What's this?

Check These Out

Stay in the loop…

All commands (14,187)

sorted by