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awk, bash, curl, find, grep, Linux, sed
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Functions

All commands from sorted by
Terminal - All commands - 12,420 results
ls -1t | head -n10
2009-06-23 12:15:12
User: wires
Functions: head ls
Tags: ls
7
Up
Down
find the 10 latest (modified) files

order the files by modification (thanks stanishjohnd) time, one file per output line and filter first 10

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ditto --arch i386 doubleTwist.app doubleTwist_i386.app
2009-06-22 23:59:14
User: thebillywayne
0
Up
Down
remove unnecessary architecture code from Mac OS X Universal binaries

ditto can be used to "thinnify" Mach-O Universal binaries to separate unncessary code from your machine. For example, doubleTwist.app shaved off around 10 MB while Google Earth went from 112 MB to 62 MB after extracting only the i386 code from them.

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ssh -L :: -L :: @
2009-06-22 19:12:48
User: starchox
Functions: ssh
10
Up
Down
Multiple SSH Tunnels

Thankfully, the ssh command allows you to specify multiple tunnels through the same server in one command.

Remeber if you want a priviliged port on your machine, you must use root or sudo account.

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wget -q --user=<username> --password=<password> 'https://updates.opendns.com/nic/update?hostname=your_opendns_hostname&myip=your_ip' -O -
2009-06-22 18:08:42
User: Alanceil
Functions: wget
Tags: IP OpenDNS Dynamic IP
5
Up
Down
Update your OpenDNS network ip

Intended for dynamic ip OpenDNS users, this command will update your OpenDNS network IP.

For getting your IP, you can use one of the many one-liners here on commandlinefu.

Example:

I use this in a script which is run by kppp after it has successfully connected to my ISP:

---

#!/bin/bash

IP="`curl -s http://checkip.dyndns.org/ | grep -o '[[:digit:].]\+'`"

PW="hex-obfuscated-pw-here"

if [ "$IP" == "" ] ; then echo 'Not online.' ; exit 1

else

wget -q --user=topsecret --password="`echo $PW | xxd -ps -r`" 'https://updates.opendns.com/nic/update?hostname=myhostname&myip='"$IP" -O -

/etc/init.d/ntp-client restart &

fi

---

PS: DynDNS should use a similar method, if you know the URL, please post a comment. (Something with members.dyndns.org, if I recall correctly)

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find . -name "*.sql" -print0 | wc -l --files0-from=-
2009-06-22 17:45:03
User: vincentp
Functions: find wc
Tags: find wc count line
2
Up
Down
Get lines count of a list of files

This command gives you the number of lines of every file in the folder and its subfolders matching the search options specified in the find command. It also gives the total amount of lines of these files.

The combination of print0 and files0-from options makes the whole command simple and efficient.

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multitail /var/log/messages /var/log/apache2/access.log /var/log/mail.info
2009-06-22 06:51:11
User: Neo23x0
4
Up
Down
Watch several log files in a single window

It works like a "tail -f" on several files.

Use the number keys 0-9 to set a baseline in the numbered window.

Pressing "b" let you scroll back in one of the windows.

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while true; do { $(which logger) -p local4.notice `free -m | grep Mem`; sleep 60; } done &
2009-06-22 00:29:53
User: Neo23x0
Functions: grep sleep which
3
Up
Down
Log the current memory statistics frequently to syslog

Uses logger in a while loop to log memory statistics frequently into the local syslog server.

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bind '"\e[24~"':"\"ps -elF;df -h;free -mt;netstat -lnpt;who -a\C-m"""
2009-06-21 23:57:20
User: Neo23x0
17
Up
Down
Create a system overview dashboard on F12 key

Command binds a set of commands to the F12 key.

Feel free to alter the dashboard according to your own needs.

How to find the key codes?

Type

read

Then press the desired key (example: F5)

^[[15~

Try

bind '"\e[15~"':"\"ssh [email protected]\C-m"""

or

bind '"\e[16~"':"\"apachectl -k restart\C-m"""
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!*
2009-06-21 17:58:01
User: Neo23x0
86
Up
Down
Reuse all parameter of the previous command line

!* is all of the arguments to the previous command rather than just the last one.

This is useful in many situations.

Here's a simple example:

vi cd /stuff

oops!

[exit vi, twice]

!*

expands to: cd /stuff

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# cd $partition; dd if=/dev/zero of=ShredUnusedBlocks bs=512M; shred -vzu ShredUnusedBlocks
2009-06-21 14:17:22
User: mpb
Functions: cd dd shred
8
Up
Down
securely erase unused blocks in a partition

This command securely erases all the unused blocks on a partition.

The unused blocks are the "free space" on the partition.

Some of these blocks will contain data from previously deleted files.

You might want to use this if you are given access to an old computer and you do not know its provenance.

The command could be used while booted from a LiveCD to clear freespace space on old HD.

On modern Linux LiveCDs, the "ntfs-3g" system provides ReadWrite access to NTFS partitions thus enabling this method to also be used on Wind'ohs drives.

NB depending on the size of the partition, this command could take a while to complete.

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sudo sed 's/\o0/\n/g' "/proc/$(pidof -x firefox)/environ" ;# replace firefox
2009-06-21 09:47:02
User: plasticdoc
Functions: sed sudo
3
Up
Down
Show an application's environment variables
Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
watch -t -n1 "date +%T|figlet"
2009-06-21 01:02:37
User: dennisw
Functions: watch
Tags: Linux terminal unix shell date time figlet watch
45
Up
Down
Display a cool clock on your terminal

This command displays a clock on your terminal which updates the time every second. Press Ctrl-C to exit.

A couple of variants:

A little bit bigger text:

watch -t -n1 "date +%T|figlet -f big"

You can try other figlet fonts, too.

Big sideways characters:

watch -n 1 -t '/usr/games/banner -w 30 $(date +%M:%S)'

This requires a particular version of banner and a 40-line terminal or you can adjust the width ("30" here).

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sudo pmset -a hibernatemode 1
2009-06-20 22:52:10
User: thebillywayne
Functions: sudo
-1
Up
Down
Mac OS X (laptops ??) only : control hibernation state more easily from Terminal.app

sudo pmset -a hibernatemode 1 sets hiberate on.

sudo pmset -a hibernatemode 0 sets hibernate off.

from the pmset man page:

0001 (bit 0) enables hibernation; causes OS X to write memory state to

hibernation image at sleep time. On wake (without bit 1 set) OS X will

resume from the hibernation image. Bit 0 set (without bit 1 set) causes

OS X to write memory state and immediately hibernate at sleep time.

I often change my MacBook's sleep state. So I created a function for bash to make it a little easier.

Usage:

hibernate (on | off)

"hibernate on" will set your laptop to hibernate if the lid is closed.

"hibernate off" will set your laptop to sleep if the lid is closed.

### note : "proper" indentation isn't preserved on the website

function hibernate()

{

case "${1}" in

on)

sudo pmset -a hibernatemode 1

echo Hibernate mode on.

;;

off)

sudo pmset -a hibernatemode 0

echo Hiberate mode off.

;;

*)

echo "I'm sorry Dave, but I can't do that."

;;

esac

}

To make things easier, add the proper line in your /etc/sudoers file so that your user may invoke pmset without a password. Here's how mine looks:

bwayne luna = NOPASSWD: /usr/bin/pmset

Don't forget that you must edit sudoers with `sudo visudo` from Terminal.app, and not by another text editor.

Sorry this is so Mac OS specific.

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svn status | grep '!' | sed 's/!/ /' | xargs svn del --force
2009-06-20 13:01:07
User: tarzantiger
Functions: grep sed xargs
2
Up
Down
Deleting Files from svn which are missing
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mplayer dvdnav:// -dvd-device foo.img -mouse-movements
2009-06-19 23:03:04
User: dezza
3
Up
Down
Play ISO/DVD-files and activate dvd-menu and mouse menu clicks.
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
unrar p -inul foo.rar|mplayer -
2009-06-19 22:40:01
User: dezza
5
Up
Down
On-the-fly unrar movie in .rar archive and play it, does also work on part archives.
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ffmpeg -an -f video4linux -s 320x240 -b 800k -r 15 -i /dev/v4l/video0 -vcodec mpeg4 myvideo.avi
2009-06-19 17:41:43
User: dcabanis
Tags: video ffmpeg codec webcam
3
Up
Down
Record a webcam output into a video file.

The option -an disables audio recording, -f forces the use of video4linux for the input, -s sets the video to the size 320x240, -b sets the recording bitrate, -r sets the frame rate to 15fps, -i gives the input device, -vcodec sets the output format.

Press Q to stop recording or you can specify the recording time with the -t option like -t 00:1:30

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mencoder video.avi lavc -lavcopts vcodec=mpeg4:vbitrate=800 newvideo.avi
2009-06-19 17:30:46
User: dcabanis
Tags: video mencoder codec
1
Up
Down
Encode a file to MPEG4 format

Encode video.avi into newvideo.avi using the libav codec to produce an MPEG4 file with a bitrate of 800

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mencoder -tv device=/dev/video1 tv:// -ovc copy -o video.avi
2009-06-19 17:21:33
User: dcabanis
Tags: video mencoder codec
1
Up
Down
Record camera's output to a avi file

video.avi is the resulting file. Press Ctrl+c to stop the recording. You can change the OVC option to another to record into a different format.

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sed -n '/START/,${/STOP/q;p}'
2009-06-19 15:27:36
User: mungewell
Functions: sed
Tags: sed grep
3
Up
Down
Efficiently extract lines between markers

GNU Sed can 'address' between two regex, but it continues parsing through to the end of the file. This slight alteration causes it to terminate reading the input file once the STOP match is made.

In my example I have included an extra '/START/d' as my 'start' marker line contains the 'stop' string (I'm extracting data between 'resets' and using the time stamp as the 'start').

My previous coding using grep is slightly faster near the end of the file, but overall (extracting all the reset cycles in turn) the new SED method is quicker and a lot neater.

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ga
2009-06-19 12:20:10
User: miccaman
Tags: vim
-5
Up
Down
vim display hex value char under cursor
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:r! echo %
2009-06-19 12:17:28
User: miccaman
Functions: echo
Tags: vim
1
Up
Down
vim insert current filename

insert filename

Normal mode: "%p

Insert mode: %

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:source ~/.vimrc
2009-06-19 12:14:55
User: miccaman
Tags: vim
3
Up
Down
load changes without logging in and out vim

src: daily vim blog

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:set nomore :argdo %s/foo/bar/g | update
2009-06-19 12:12:33
User: miccaman
Tags: vim
2
Up
Down
%s across multiple files with Vim

src: http://www.ibrahim-ahmed.com/2008/01/find-and-replace-in-multiple-files-in.html

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dpkg -l 'linux-*' | sed '/^ii/!d;/'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d;s/^[^ ]* [^ ]* \([^ ]*\).*/\1/;/[0-9]/!d'
2009-06-19 10:23:38
User: plasticdoc
Functions: sed
Tags: Linux sed dpkg
4
Up
Down
show installed but unused linux headers, image, or modules

will show:

installed linux headers, image, or modules: /^ii/!d

avoiding current kernel: /'"$(uname -r | sed "s/\(.*\)-\([^0-9]\+\)/\1/")"'/d

only application names: s/^[^ ]* [^ ]* \([^ ]*\).*/\1/

avoiding stuff without a version number: /[0-9]/!d

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