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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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what model of computer I'm using?

Big (four-byte) $RANDOM

Sometimes, in a shell script, you need a random number bigger than the range of $RANDOM. This will print a random number made of four hex values extracted from /dev/urandom.

Binary search/replace

Replace all instances of "A" with "B" in file "source" saved as file "destination". !! IF A/B is multi-byte, then separate bytes with spaces like so: "s/20\ 0A/00/g".

which process has a port open

Find the process you are looking for minus the grepped one

preferred way to query ps for a specific process name (not supported with all flavors of ps, but will work on just about any linux afaik)

Do some learning...

I like it sorted... 2> /dev/null was also needless, since our pipes already select stdin, only.

macOS: Save disk space by moving apps to external drives

Because Mac app bundles contain everything in one place, it makes running them from anywhere, including from a device such as a USB flash drive or external HDD, possible. So if your Mac has a mere 256GB of storage (as mine does), you can free up large quantities of disk space by storing apps like, say, Xcode on external devices.

Tunnel ssh through Socks Proxy

If you are blocked or need to use a Socks proxy

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

Redirect a filehandle from a currently running process.

This command uses the debugger to attach to a running process, and reassign a filehandle to a file. The two commands executed in gdb are p close(1) which closes STDOUT and p creat("/tmp/filename",0600) which creates a file and opens it for output. Since file handles are assigned sequentially, this command opens the file in place of STDOUT and once the process continues, new output to STDOUT will instead be written to our capture file.

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