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Alternative size (human readable) of files and directories (biggest last)

using mb it's still readable;) a symbol variation $ du -ms {,.[^.]}* | sort -nk1 Show Sample Output
This is sample output - yours may be different.
```
186     Foto
213     .mozilla
260     .eclipse
295     .kde
301     Desktop
```
3

du -ms * .[^.]*| sort -nk1

ioggstream · 2009-07-01 13:38:13 8

kpartx can be found inside of the multipath-tools package -a adds the mappings and -d deletes them Show Sample Output

kpartx -a /dev/mapper/space-foobar

flart · 2009-07-01 09:53:33 8

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.
This is sample output - yours may be different.
13

lsof -i

unixmonkey4503 · 2009-06-30 22:36:00 8
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.
This is sample output - yours may be different.
9

On target: "nc -l 4000 | tar xvf -" On source: "tar -cf - . | nc target_ip 4000"

tiagofischer · 2009-06-30 19:36:19 8
Alternative size (human readable) of directories (biggest first)

Taken from http://www.earthinfo.org/linux-disk-usage-sorted-by-size-and-human-readable/
This is sample output - yours may be different.
-3

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}' }

illicium · 2009-06-30 19:20:30 15
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
This is sample output - yours may be different.
2

grep -v "\ *#\|^$" /etc/path/to.config

geekboxjockey · 2009-06-30 18:14:46 17
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.
This is sample output - yours may be different.
4

for file in *.pem; do ln -s $file `openssl x509 -hash -noout -in $file`.0; done

darkpand · 2009-06-30 17:42:07 98
Matrix Style
This is sample output - yours may be different.
67

tr -c "[:digit:]" " " < /dev/urandom | dd cbs=$COLUMNS conv=unblock | GREP_COLOR="1;32" grep --color "[^ ]"

allinurl · 2009-06-30 17:23:49 25
Recursive when needed

avoid rm to be recursive until you complete the command: put the -rf at the end!
This is sample output - yours may be different.
-3

rm strangedirs -rf

ioggstream · 2009-06-30 15:10:31 15
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
This is sample output - yours may be different.
2

ls /mnt/badfs &

ioggstream · 2009-06-30 14:40:22 9
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
This is sample output - yours may be different.
```
^_^ # true
^_^ # false
-_- #
```
17

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)"

digitalsushi · 2009-06-30 14:29:55 376
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
This is sample output - yours may be different.
6

cp -bfS.bak filename filename

ioggstream · 2009-06-30 14:17:28 33
stop windows update

Windows only: stops windows update and the nagging restart window. You need your admin password for this one.
This is sample output - yours may be different.
4

runas /user:administrator net stop wuauserv

oernii2 · 2009-06-30 09:29:03 18
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
This is sample output - yours may be different.
-6

source ~/.bash_profile

unixmonkey743 · 2009-06-29 19:26:43 16
Trim linebreaks
This is sample output - yours may be different.
2

cat myfile.txt | tr -d '\n'

Cowboy · 2009-06-29 12:49:08 6
SVN Status log to CSV

Note you have also the --xml option ;) Show Sample Output
This is sample output - yours may be different.
```
1 | author | 2009-09-09 12:12:12 +200 | Initial import
2 | author | 2009-09-09 12:15:16 +200 | ADDED: great feature
```
3

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

Cowboy · 2009-06-29 12:48:30 6
Define a quick calculator function

defines a handy function for quick calculations from cli. once defined: ? 10*2+3 Show Sample Output
This is sample output - yours may be different.
```
23?
```
58

? () { echo "$*" | bc -l; }

fizz · 2009-06-28 20:15:30 27
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. '?').
This is sample output - yours may be different.
3

for i in *;do mv "$i" "$(echo $i | sed s/PROBLEM/FIX/g)";done

AlecSchueler · 2009-06-28 01:50:25 18
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.
This is sample output - yours may be different.
68

rename 'y/ /_/' *

signal9 · 2009-06-27 22:20:47 83

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

curl -u YourUsername:YourPassword -d status="Your status message go here" http://twitter.com/statuses/update.xml

m33600 · 2009-06-27 21:47:48 12

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
This is sample output - yours may be different.
```
(...) |$banghead$|$bear$|$beer$|$blush$|$bow$|$bricklayers$|$brokenheart$|$bug$|$bye$|$cake$|$call$|$cash$|$chuckle$| (...)
```
1

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

alvieboy · 2009-06-26 20:03:17 6
Print line immediately before a matching regex.

Use this if you don't have access to GNU grep's -B option.
This is sample output - yours may be different.
4

awk '/regex/{print x};{x=$0}'

res0nat0r · 2009-06-26 19:29:54 10
VIM: Replace a string with an incrementing number between marks 'a and 'b (eg, convert string ZZZZ to 1, 2, 3, ...)
This is sample output - yours may be different.
11

:let i=0 | 'a,'bg/ZZZZ/s/ZZZZ/\=i/ | let i=i+1

res0nat0r · 2009-06-26 19:23:29 6
Move files around local filesystem with tar without wasting space using an intermediate tarball.
This is sample output - yours may be different.
7

( cd SOURCEDIR && tar cf - . ) | (cd DESTDIR && tar xvpf - )

res0nat0r · 2009-06-26 19:13:51 14

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

pax -r -s ',^/,,' -f file.tar

res0nat0r · 2009-06-26 19:10:57 7

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Convert CSV to JSON

Replace 'csv_file.csv' with your filename.

Random Number Between 1 And 256

It takes a byte from /dev/random whose source is the kernel entropy pool (better source than other solutions).

function to verify an IP address - can be used at the shell prompt or in a shell script

When processing IP addresses in the shell (or shell script) it is useful to be able to verify that the value of data is an IP address (an not some random string or non-sensible IP address).

do 'foo' until it exits successfully, pausing in between crashes

restart a buggy script when it dies. works great for "git svn fetch", which leaks memory like a sieve and eventually dies...making you restart it.

Generate random valid mac addresses

Shorter and more straightforward. Also in perl: $ perl -e 'print join(":", map { sprintf "%0.2X",rand(256) }(1..6))."\n"'

Matrix Style

I like the fact the Patola's version uses only ones and zeros, but I also like the sparse output of the other versions. This one combines both of those features and eliminates some unnecessary cruft. You can vary the sparseness by changing "$(($RANDOM % 5))" to another number. The number in this term "$(($RANDOM % 4))" controls how frequently the numbers are output bold.

Execute a command with the last parameter of a previous command

Suppose that you had change in a directory like /home/user/mycode/code, and now you need to list it, instead of type entire path again, use ls !$ to recall path and list. Useful with many commands, this is only an example. (In this case, same result can be achivied with ls .)

Remove all unused kernels with apt-get

Note the double space: "...^ii␣␣linux-image-2..." Like 5813, but fixes two bugs: [1]This leaves the meta-packages 'linux-headers-generic' and 'linux-image-generic' alone so that automatic upgrades work correctly in the future. [2]Kernels newer than the currently running one are left alone (this can happen if you didn't reboot after installing a new kernel). I'm bummed that this took 228 characters. I'd like to see a simpler version.

Convert CSV to JSON

Replace 'csv_file.csv' with your filename.

Convert one file from ISO-8859-1 to UTF-8.

Nothing fancy it just converts one file from one character encoding into another one.

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