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All commands

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Terminal - All commands - 10,565 results
while true; do netstat -a|grep WAIT|wc -l; sleep 5; done
2013-06-19 09:19:41
User: adimania
Functions: grep netstat sleep wc
Tags: netstat tcp
0
Up
Down
One liner to check out CLOSE_WAIT and TIME_WAIT connection every five seconds while debugging network apps

This has saved me many times while debugging timeout issues to "too many open files" issues. A high number of the order of thousand, indicates that somewhere connection is not being closed properly.

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ps -eo pid,lstart,cmd
2013-06-17 12:52:53
User: kruspemsv
Functions: ps
Tags: PID
7
Up
Down
Discover the process start time

That is useful to discover the start time of process older than 1 day.

You can also run:

ls -ld /proc/PID

That's returning the creation date of the proc files from the process. Some users reported that this way might show you a wrong date since any other process like cron, for example, could change this date.

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
rcs_changes(){ rcsdiff -y --suppress-common-lines "$1" 2>/dev/null | cut -d'|' -f2; }
2013-06-16 19:16:40
User: return13
Functions: cut
0
Up
Down
Shows you changes of an RCS file
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
stat -f -L -c %T YOUR_FILE_OR_DIRECTORY
2013-06-14 07:27:41
User: Koobiac
Functions: stat
Tags: stat format
1
Up
Down
Display the format of a directory or file
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
git branch -r | awk '{print $1}' | egrep -v -f /dev/fd/0 <(git branch -vv | grep origin) | awk '{print $1}' | xargs git branch -d
2013-06-10 17:56:20
User: Schleis
Functions: awk egrep grep xargs
Tags: git
1
Up
Down
Remove git branches that do not have a remote tracking branch anymore
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
wlanconfig <wireless_device> list sta
2013-06-08 13:46:51
User: quitaiskiluisf
Tags: wireless stations clients
0
Up
Down
List wireless clients connected to an access point

When the wireless card is in AP mode, list the users which are connected to the network.

Show sample output | Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
iwpriv ath<x> kickmac <macaddress>
2013-06-08 13:41:24
User: quitaiskiluisf
Tags: wireless wifi atheros disconnect mac disconnect user
1
Up
Down
Disconnect a wireless client on an atheros-based access point

This command will disconnect the user whose mac was specified from the current list of clients from the wireless network when the network card is working in access point mode. Works on atheros-based access points which use the madwifi driver (not sure, but don't think it will work on access points which are not atheros-based, as it uses the atheros's iwpriv extensions).

It will not prevent the user from reconnecting to the network, but may force the user to roam to another AP, with stronger signal.

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
Shift ZZ
2013-06-06 14:33:44
User: techie
-7
Up
Down
Save and quit the easy way
Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
avconv -y -f x11grab -r 12 -s 1600x900 -i :0.0 -f video4linux2 -i /dev/video0 -f alsa -i pulse -map 0:0 -vcodec rawvideo -pix_fmt yuv420p desktop.y4m -map 1:0 -vcodec rawvideo -pix_fmt yuv420p camera.y4m -map 2:0 audio.mp3
2013-05-26 13:36:55
User: alikhalil
Tags: video capture avconv
0
Up
Down
Capture desktop at resolution 1600x900 and camera video files also captures mic audio to file

Use avconv linux package to record input from camera, mic, and desktop for creating instructional videos. The generated video and audio files will required further processing to put in to a single useable video.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo $[RANDOM % 2]
2013-05-25 19:15:57
User: anapsix
Functions: echo
Tags: bash random boolean scripting
4
Up
Down
get a random 0/1, use it for on/off, yes/no

use it to add a random boolean switch to your script

Show sample output | Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo $[RANDOM % 100] # range 0-99
2013-05-25 19:02:00
User: anapsix
Functions: echo
Tags: bash cronjob random crontab
-2
Up
Down
get a random number in bash

use it to stagger cronjob or to get a random number

increase the range by replacing 100 with your own max value

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
nohup tail /var/log/murmur.log | perl -ne '/^<.>[0-9:. -]{24}(\d+ => )?(.*)/; $pid=`pgrep -u murmur murmurd | head`; chomp $pid; `logger -p info -t "murmurd[$pid]" \\"$2\\"`;' &
2013-05-25 01:12:52
User: MagisterQuis
Functions: info nohup perl tail
Tags: murmur mumble murmurd OpenBSD
0
Up
Down
Send murmurd log lines to syslog

Sends log lines from murmur's (the mumble server's) logfile to syslog.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
sshpass -p "YOUR_PASSWORD" ssh -o StrictHostKeyChecking=no YOUR_USERNAME@SOME_SITE.COM
2013-05-24 14:33:38
User: o0110o
Functions: ssh
Tags: ssh Linux apt-get login password sshpass
3
Up
Down
SSH Auto-login with password

You need to install "sshpass" for this to work.

apt-get install sshpass

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
du -xB M --max-depth=2 /var | sort -rn | head -n 15
2013-05-23 10:45:21
User: bouktin
Functions: du head sort
Tags: bash Linux du
2
Up
Down
list the top 15 folders by decreasing size in MB

list the top 15 folders by decreasing size in MB

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
nocache <I/O-heavy-command>
2013-05-21 15:15:05
User: michelsberg
Tags: nice cache ionice nocache I/O cachedel cachestats
19
Up
Down
prevent large files from being cached in memory (backups!)

We all know...

nice -n19

for low CPU priority.

 

ionice -c3

for low I/O priority.

 

nocache can be useful in related scenarios, when we operate on very large files just a single time, e.g. a backup job. It advises the kernel that no caching is required for the involved files, so our current file cache is not erased, potentially decreasing performance on other, more typical file I/O, e.g. on a desktop.

 

http://askubuntu.com/questions/122857

https://github.com/Feh/nocache

http://packages.debian.org/search?keywords=nocache

http://packages.ubuntu.com/search?keywords=nocache (seems to be unavailable in ubuntu...)

 

To undo caching of a single file in hindsight, you can do

cachedel <OneSingleFile>

 

To check the cache status of a file, do

cachestats <OneSingleFile>
Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find -name '*.mp3' -exec mp3info {} -p "%F: %r kbps\n" \; | sort | sed '/320 kbps/d'
2013-05-21 04:46:55
User: infojunkie
Functions: find sed sort
2
Up
Down
List mp3 files with less than 320 kbps bitrate.
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find . -type f -name filename.exe -exec sed -i "s/oldstring/oldstring/g" {} +;
2013-05-20 19:17:10
User: eddieb
Functions: find sed
Tags: sed find regex find text search and replace
0
Up
Down
Recursively search and replace old with new string, inside every instance of filename.ext

This is a slightly modified version of http://www.commandlinefu.com/commands/view/4283/recursive-search-and-replace-old-with-new-string-inside-files (which did not work due to incorrect syntax) with the added option to sed inside only files named filename.ext

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
url=http://mirrors.mageia.org/api/mageia.3.i586.list; wget -q ${url} -O - | grep rsync:
2013-05-20 16:19:05
User: mpb
Functions: grep wget
0
Up
Down
Get a list of Mageia Linux mirrors providing rsync connectivity for Mageia 3 release

Need to find a Mageia Linux mirror server providing Mageia 3 via rsync?

Modify the "url=" string for the version you want. This shows i586 which is the 32bit version.

If you want the 64bit version it is:

url=http://mirrors.mageia.org/api/mageia.3.x86_64.list; wget -q ${url} -O - | grep rsync:

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
php -S 127.0.0.1:8080
2013-05-19 11:23:17
User: VictorBjelkholm
11
Up
Down
Run the built in PHP-server in current folder

You must have PHP 5.4.0 or later to be able to run the built in server.

This web server is designed for developmental purposes only, and should not be used in production.

URI requests are served from the current working directory where PHP was started, unless the -t option is used to specify an explicit document root. If a URI request does not specify a file, then either index.php or index.html in the given directory are returned. If neither file exists, then a 404 response code is returned.

If a PHP file is given on the command line when the web server is started it is treated as a "router" script. The script is run at the start of each HTTP request. If this script returns FALSE, then the requested resource is returned as-is. Otherwise the script's output is returned to the browser.

Standard MIME types are returned for files with extensions: .css, .gif, .htm, .html, .jpe, .jpeg, .jpg, .js, .png, .svg, and .txt. The .htm and .svg extensions are recognized from PHP 5.4.4 onwards.

More information here: http://php.net/manual/en/features.commandline.webserver.php

Show sample output | Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
startx &! exit
2013-05-18 21:41:16
User: dash
Tags: X
2
Up
Down
Avoid killing the X server with CTRL+C on the tty it was started from
Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
pwgen -Bs 10 1
2013-05-16 10:50:00
User: techie
Tags: Security password sha256 /dev/urandom md5deep
-6
Up
Down
Create a secure password using /dev/urandom and sha256
Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
until !!; do :; done
2013-05-14 18:08:54
User: unixmonkey21806
22
Up
Down
Retry the previous command until it exits successfully
Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
vimhtml() { [[ -f "$1" ]] || return 1; vim +'syn on | run! syntax/2html.vim | wq | q' "$1";}
2013-05-12 19:30:51
User: RanyAlbeg
Functions: return vim
4
Up
Down
Use Vim to convert text to HTML.

``vimhtml somefile.txt`` will open vim for the HTML convertion and close it immediately after its done, leaving you with somefile.html which you can later use in your website or whatever.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
mplayer -af volume=10.1:0 $movie
2013-05-11 20:47:50
User: hendry
0
Up
Down
Amplify movie playback

If a movie is too hard to hear, try the above command to make it louder.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo lowercaseword | tr '[a-z]' '[A-Z]'
2013-05-11 11:08:37
User: eastwind
Functions: echo tr
-1
Up
Down
convert a string from lower case into uppercase
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate