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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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wget download with multiple simultaneous connections

Grab all .flv files from a webpage to the current working directory

I wanted all the 'hidden' .flv files from the http link in the command line; wget seemed appropriate, fed with output from lynx, grep the flv files and the normalised via sed (to remove the numeric bullet). Similar to the 'Grab mp3 files' fu. Replace link with your own, grep arg with something more interesting ;) See here for something along the same lines... http://www.commandlinefu.com/commands/view/1006/grab-mp3-files-from-your-favorite-netcasts-mp3blog-or-sites-that-often-have-good-mp3s Hope you find it useful! Improvements welcome, naturally.

Find 'foo' string inside files

Get AWS temporary credentials ready to export based on a MFA virtual appliance

You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

See how many more processes are allowed, awesome!

There is a limit to how many processes you can run at the same time for each user, especially with web hosts. If the maximum # of processes for your user is 200, then the following sets OPTIMUM_P to 100. $ OPTIMUM_P=$(( (`ulimit -u` - `find /proc -maxdepth 1 $ -user $USER -o -group $GROUPNAME $ -type d|wc -l`) / 2 )) This is very useful in scripts because this is such a fast low-resource-intensive (compared to ps, who, lsof, etc) way to determine how many processes are currently running for whichever user. The number of currently running processes is subtracted from the high limit setup for the account (see limits.conf, pam, initscript). An easy to understand example- this searches the current directory for shell scripts, and runs up to 100 'file' commands at the same time, greatly speeding up the command. $ find . -type f | xargs -P $OPTIMUM_P -iFNAME file FNAME | sed -n '/shell script text/p' I am using it in my http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html especially for the xargs command. Xargs has a -P option that lets you specify how many processes to run at the same time. For instance if you have 1000 urls in a text file and wanted to download all of them fast with curl, you could download 100 at a time (check ps output on a separate [pt]ty for proof) like this: $ cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}' I like to do things as fast as possible on my servers. I have several types of servers and hosting environments, some with very restrictive jail shells with 20processes limit, some with 200, some with 8000, so for the jailed shells my xargs -P10 would kill my shell or dump core. Using the above I can set the -P value dynamically, so xargs always works, like this. $ cat url-list.txt | xargs -I '{}' -P $OPTIMUM_P curl -O '{}' If you were building a process-killer (very common for cheap hosting) this would also be handy. Note that if you are only allowed 20 or so processes, you should just use -P1 with xargs.

'Fix' a typescript file created by the 'script' program to remove control characters

attribution: Thanks to repellent on perlmonks.org source: http://www.perlmonks.org/?node_id=684459

Number of CPU's in a system

this works for a Linux based system, other UNIX systems may have other way(s) to check the number of CPUs.

To find the count of each open file on a system (that supports losf)

determine if a shared library is compiled as 32bit or 64bit

Determines the flavor of a shared library by looking at the addresses of its exposed functions and seeing if they are 16 bytes or 8 bytes long. The command is written so the library you are querying is passed to a variable up font -- it would be simple to convert this to a bash function or script using this format.

Search replace with Ansible style timestamps

$ ls httpd.conf httpd.conf.2015-07-22@14:43:20

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