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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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Get a list of Mageia Linux mirrors providing rsync connectivity for Mageia 4 release

Need to find a Mageia Linux mirror server providing Mageia 4 via rsync? Modify the "url=" string for the version you want. This shows i586 which is the 32bit version. If you want the 64bit version it is: url=http://mirrors.mageia.org/api/mageia.4.x86_64.list; wget -q ${url} -O - | grep rsync:

Clear filesystem memory cache

erase content from a cdrw

Ctrl+S Ctrl+Q terminal output lock and unlock

These are simple shortcuts to pause and continue terminal output, works in most terminals and screen multiplexers like screen. You can use it to catch something if things change too fast, and scroll with Shift + PgUp PgDown. On linux console ScrollLock can also be used.

Display IP : Count of failed login attempts

The lastb command presents you with the history of failed login attempts (stored in /var/log/btmp). The reference file is read/write by root only by default. This can be quite an exhaustive list with lots of bots hammering away at your machine. Sometimes it is more important to see the scale of things, or in this case the volume of failed logins tied to each source IP. The awk statement determines if the 3rd element is an IP address, and if so increments the running count of failed login attempts associated with it. When done it prints the IP and count. The sort statement sorts numerically (-n) by column 3 (-k 3), so you can see the most aggressive sources of login attempts. Note that the ':' character is the 2nd column, and that the -n and -k can be combined to -nk. Please be aware that the btmp file will contain every instance of a failed login unless explicitly rolled over. It should be safe to delete/archive this file after you've processed it.

Create QR codes from a URL.

QR codes are those funny square 2d bar codes that everyone seems to be pointing their smart phones at. Try the following... $ qrurl http://xkcd.com Then open qr.*.png in your favorite image viewer. Point your the bar code reader on your smart phone at the code, and you'll shortly be reading xkcd on your phone. URLs are not the only thing that can be encoded by QR codes... short texts (to around 2K) can be encoded this way, although this function doesn't do any URL encoding, so unless you want to do that by hand it won't be useful for that.

Bitcoin Brainwallet Private Key Calculator

A bitcoin "brainwallet" is a secret passphrase you carry in the "wallet" of your brain. The Bitcoin Brainwallet Private Key Calculator calculates the standard base58 encoded bitcoin private key from your "brainwallet" passphrase. The private key is the most important bitcoin number. All other numbers can be derived from it. This command uses 3 other functions - all 3 are defined on my user page: 1) brainwallet_exponent() - search for Bitcoin Brainwallet Exponent Calculator 2) brainwallet_checksum() - search for Bitcoin Brainwallet Exponent Calculator 3) b58encode() - search for Bitcoin Brainwallet Base58 Encoder Do make sure you use really strong, unpredictable passphrases (30+ characters)! http:brainwallet.org can be used to check the accuracy of this calculator.

prevent accidents while using wildcards

alternative for "echo rm *.txt". Just doubletab the command you are willing to use and it will show you the affected files.

Convert seconds to [DD:][HH:]MM:SS

Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

vmstat/iostat with timestamp

Also useful with iostat, or pretty much anything else you want timestamped.

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