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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 84

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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Poor man's ntpdate

Convert a MOV captured from a digital camera to a smaller AVI

Convert those .mov files that your digital camera makes to .avi Adjust the bitrate (-b) to get the appropriate file size. A larger bitrate produces a larger (higher quality) .avi file and smaller bitrate produces a smaller (lower quality) .avi file. Requires ffmpeg (see man page for details) (tested with canon camera MOV files) Other examples: $ffmpeg -i input.mov -sameq -vcodec msmpeg4v2 -acodec pcm_u8 output.avi $ffmpeg -i input.mov -b 1024k -vcodec msmpeg4v2 -acodec pcm_u8 output.avi

Change to $HOME - zsh, bash4

To change to $HOME in that manner you need to set a shell option. In zsh it is auto_cd, hence $ setopt -o auto_cd in bash4 it is autocd, hence $ shopt -s autocd What the option does is allow you to cd to a directory by just entering its name. This also works if the directory name is stored in a variable: $ www=/var/www/lighttpd; $www sends you to /var/www/lighttpd. CAUTION: If a command or function name identical to the directory name exists it takes precedence.

ionice limits process I/O, to keep it from swamping the system (Linux)

This command is somewhat similar to 'nice', but constrains I/O usage rather than CPU usage. In particular, the '-c3' flag tells the OS to only allow the process to do I/O when nothing else is pending. This dramatically increases the responsiveness of the rest of the system if the process is doing heavy I/O. There's also a '-p' flag, to set the priority of an already-running process.

processes per user counter

enumerates the number of processes for each user. ps BSD format is used here , for standard Unix format use : ps -eLf |awk '{$1} {++P[$1]} END {for(a in P) if (a !="UID") print a,P[a]}'

remove password from openssl key file

Strip a password from a openssl key to use with apache httpd server

Alert visually until any key is pressed

I learned a few things reading this command. But I did run into a few issues: 1. On systems that don't use GNU echo (e.g. macOS 10.14.5 Mojave), the e option may not be supported. In this case ANSI escape codes will echoed as text and the terminal will not flash, like this: \e[?5h\e[38;5;1m A L E R T Thu Jun 20 16:31:29 PDT 2019 2. Since the read command strips\ignores leading backslashes, if a user types the backslash character once in the loop, it will not break. Typing backslash twice in a loop will break as expected. 3. The foreground color is set to red (\e[38;5;1m) on every loop. This could be set once before we call while, and then reset once when the loop breaks. 4. Instead of resetting the foreground color when it breaks, the video mode is set back to normal (\e[?5l). This has the effect of leaving the terminal text red until it is manually reset. The alternative I'm proposing here addresses these issues. I tested it on macOS and Arch Linux.

grep across a git repo and open matching files in gedit

This command can be used to extract the IP address of the network.

can be used within a script to configure iptables for example: iface=$2 inet_ip=`ifconfig "$iface" | grep inet | cut -d: -f2 | cut -d ' ' -f1` ipt="sudo /sbin/iptables" ......................... ---------------------------------------------------------------------------------------------------------------- $ipt -A INPUT -i $iface ! -f -p tcp -s $UL -d $inet_ip --sport 1023: --dport 3306 -m state --state NEW,ESTABLISHED -j ACCEPT ---------------------------------------------------------------------------------------------------------------- ----------------------------------------------------------------------------------------------------------------- $ipt -A OUTPUT -o $iface -p tcp -s $inet_ip -d $UL --sport 3306 --dport 1023: -m state --state ESTABLISHED,RELATED -j ACCEPT -----------------------------------------------------------------------------------------------------------------

Create a mirror of a local folder, on a remote server

Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

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