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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
kpartx -a /dev/mapper/space-foobar
2009-07-01 09:53:33
User: flart
1
Up
Down
Access partitions inside a LVM volume

kpartx can be found inside of the multipath-tools package

-a adds the mappings and -d deletes them

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
lsof -i
2009-06-30 22:36:00
User: unixmonkey4503
13
Up
Down
List programs with open ports and connections

I prefer to use this and not the -n variety, so I get DNS-resolved hostnames. Nice when I'm trying to figure out who's got that port open.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
On target: "nc -l 4000 | tar xvf -" On source: "tar -cf - . | nc target_ip 4000"
2009-06-30 19:36:19
User: tiagofischer
Tags: tar nc
9
Up
Down
Using netcat to copy files between servers

It bypasses encryption overhead of SSH and depending on configuration can be significantly faster.

It's recommended to use only in trusted networks.

Comments (81) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
function duf { du -k $@ | sort -rn | perl -ne '($s,$f)=split(/\t/,$_,2);for(qw(K M G T)){if($s<1024){$x=($s<10?"%.1f":"%3d");printf("$x$_\t%s",$s,$f);last};$s/=1024}' }
2009-06-30 19:20:30
User: illicium
Functions: du perl sort
Tags: less sort find du human
-3
Up
Down
Alternative size (human readable) of directories (biggest first)

Taken from http://www.earthinfo.org/linux-disk-usage-sorted-by-size-and-human-readable/

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
grep -v "\ *#\|^$" /etc/path/to.config
2009-06-30 18:14:46
User: geekboxjockey
Functions: grep
2
Up
Down
Dump a configuration file without comments or whitespace...

A short, *easy-er* to remember command for stripping whitespace and comments from a config file, (or any file for that matter).

Remember regex as:

slash, space, star.

pound, slash, bar.

pointy-hat, dollar. (or "caret, dollar" if you must)

:-P

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
for file in *.pem; do ln -s $file `openssl x509 -hash -noout -in $file`.0; done
2009-06-30 17:42:07
User: darkpand
Functions: file ln
Tags: openssl certificate hashing
4
Up
Down
c_rehash replacement

When you don't have c_rehash handy. Really simple - if you have a .pem file that doesn't really contain a x509 cert (let's say, newreq.pem), it will create a link, simply called '.0', pointing to that file.

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
tr -c "[:digit:]" " " < /dev/urandom | dd cbs=$COLUMNS conv=unblock | GREP_COLOR="1;32" grep --color "[^ ]"
2009-06-30 17:23:49
User: allinurl
Functions: dd grep tr
Tags: color
64
Up
Down
Matrix Style
Comments (15) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
rm strangedirs -rf
2009-06-30 15:10:31
User: ioggstream
Functions: rm
Tags: rm safe
-3
Up
Down
Recursive when needed

avoid rm to be recursive until you complete the command: put the -rf at the end!

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ls /mnt/badfs &
2009-06-30 14:40:22
User: ioggstream
Functions: ls
Tags: Filesystem nfs gfs
2
Up
Down
Check if filesystem hangs

When a fs hangs and you've just one console, even # ls could be a dangerous command. Simply put a trailing "&" and play safe

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
PS1="\`if [ \$? = 0 ]; then echo \e[33\;40m\\\^\\\_\\\^\e[0m; else echo \e[36\;40m\\\-\e[0m\\\_\e[36\;40m\\\-\e[0m; fi\` \u \w:\h)"
2009-06-30 14:29:55
User: digitalsushi
18
Up
Down
Smiley Face Bash Prompt

If your last command was a dud, your bash prompt will be angry at you. Otherwise it's happy. Soon you will crave its constant approval and your linux skills will improve simply to avoid low self-esteem.

Show sample output | Comments (86) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cp -bfS.bak filename filename
2009-06-30 14:17:28
User: ioggstream
Functions: cp
6
Up
Down
quickly backup or copy a file with bash

less symbols, tab completion.

including # export SIMPLE_BACKUP_SUFFIX="_`date +%F`" in your .bashrc provides you to easily timestamp your files

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
runas /user:administrator net stop wuauserv
2009-06-30 09:29:03
User: oernii2
4
Up
Down
stop windows update

Windows only: stops windows update and the nagging restart window.

You need your admin password for this one.

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
source ~/.bash_profile
2009-06-29 19:26:43
User: unixmonkey743
-6
Up
Down
reload bash_profile

when editing .bash_profile (or .bashrc), run this to use the new version without having to exit and open a new terminal

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat myfile.txt | tr -d '\n'
2009-06-29 12:49:08
User: Cowboy
Functions: cat tr
2
Up
Down
Trim linebreaks
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
svn log | tr -d '\n' | sed -r 's/-{2,}/\n/g' | sed -r 's/ \([^\)]+\)//g' | sed -r 's/^r//' | sed -r "s/[0-9]+ lines?//g" | sort -g
2009-06-29 12:48:30
User: Cowboy
Functions: sed sort tr
3
Up
Down
SVN Status log to CSV

Note you have also the --xml option ;)

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
? () { echo "$*" | bc -l; }
2009-06-28 20:15:30
User: fizz
Functions: bc echo
Tags: bash bc function calc bc -l
57
Up
Down
Define a quick calculator function

defines a handy function for quick calculations from cli.

once defined:

? 10*2+3
Show sample output | Comments (19) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
for i in *;do mv "$i" "$(echo $i | sed s/PROBLEM/FIX/g)";done
2009-06-28 01:50:25
User: AlecSchueler
Functions: mv
Tags: bash sed mv rename encoding
3
Up
Down
Uniformly correct filenames in a directory

Useful if non-ascii characters in filenames have been improperly encoded. Replace "PROBLEM" with the incorrect characters (e.g. 'é'), and "FIX" with the correct ones (e.g. '?').

Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
rename 'y/ /_/' *
2009-06-27 22:20:47
User: signal9
Functions: rename
Tags: file rename
60
Up
Down
replace spaces in filenames with underscores

This command will replace all the spaces in all the filenames of the current directory with underscores. There are other commands that do this here, but this one is the easiest and shortest.

Comments (83) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
curl -u YourUsername:YourPassword -d status="Your status message go here" http://twitter.com/statuses/update.xml
2009-06-27 21:47:48
User: m33600
Tags: twitter
2
Up
Down
Twitter update from terminal (pok3's snipts ?)

Found it on snipt, pok3, is it yours?

I put my user = m33600, the password and the status was my robot message:

Settima robot message: ALARM ZONE 3 (sent via command line).

Now bots may have their identity on twitter...

Show sample output | Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
S=`pidof skype`;grep heap /proc/$S/maps|cut -f1 -d' '|awk -F- '{print "0x" $1 " 0x" $2}'|xargs echo "du me t ">l;gdb -batch -p $S -x l>/dev/null 2>&1;strings t|grep \(smirk|head -n1
2009-06-26 20:03:17
User: alvieboy
Functions: awk cut echo grep head xargs
1
Up
Down
Extract the emoticons regex from a running skype process

Skype has an internal regex which depicts the emoticons it supports. However you cannot simply search the binary file for it. This small 181 character line will do just that, provided skype is running. And of course, only works in linux.

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
awk '/regex/{print x};{x=$0}'
2009-06-26 19:29:54
User: res0nat0r
Functions: awk
4
Up
Down
Print line immediately before a matching regex.

Use this if you don't have access to GNU grep's -B option.

Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
:let i=0 | 'a,'bg/ZZZZ/s/ZZZZ/\=i/ | let i=i+1
2009-06-26 19:23:29
User: res0nat0r
Tags: vim
11
Up
Down
VIM: Replace a string with an incrementing number between marks 'a and 'b (eg, convert string ZZZZ to 1, 2, 3, ...)
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
( cd SOURCEDIR && tar cf - . ) | (cd DESTDIR && tar xvpf - )
2009-06-26 19:13:51
User: res0nat0r
Functions: cd tar
Tags: files
7
Up
Down
Move files around local filesystem with tar without wasting space using an intermediate tarball.
Comments (8) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
pax -r -s ',^/,,' -f file.tar
2009-06-26 19:10:57
User: res0nat0r
Functions: pax
Tags: tar
0
Up
Down
Untar file with absolute pathname to relative location

Don't have GNU tar installed that supports the redirect option (-C)? Use this.

Show sample output | Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find -L /proc/*/fd -links 0 2>/dev/null
2009-06-26 18:42:51
User: res0nat0r
Functions: find
Tags: du proc df
12
Up
Down
Find removed files still in use via /proc

Oracle DBA remove some logfiles which are still open by the database and he is complaining the space has not been reclaimed? Use the above command to find out what PID needs to be stopped. Or alternatively recover the file via:

cp /proc/pid/fd/filehandle /new/file.txt
Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate