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Numerically sorted human readable disk usage

Provides numerically sorted human readable du output. I so wish there was just a du flag for this. Show Sample Output
This is sample output - yours may be different.
```
# du -x --max-depth=1 /var | sort -n | awk '{ print $2 }' | xargs du -hx --max-depth=0
0       /var/lock
128K    /var/run
4.0K    /var/crash
4.0K    /var/games
4.0K    /var/local
4.0K    /var/opt
4.0K    /var/tmp
8.0K    /var/mail
692K    /var/spool
7.2M    /var/backups
13M     /var/log
97M     /var/www
236M    /var/lib
539M    /var/cache
891M    /var
```
4

du -x --max-depth=1 | sort -n | awk '{ print $2 }' | xargs du -hx --max-depth=0

d34dh0r53 · 2010-02-18 19:46:47 6
Speed up upgrades for a debian/ubuntu based system.

Please install aria2c before you try the above command. On ubuntu the command to install aria2c would be: sudo aptitude install aria2
This is sample output - yours may be different.
3

sudo aptitude update; sudo apt-get -y --print-uris upgrade | egrep -o -e "http://[^\']+" | sudo aria2c -c -d /var/cache/apt/archives -i -; sudo aptitude -y safe-upgrade

freethinker · 2010-02-18 16:02:29 6
Pull Total Memory Usage In Virtual Environment

This command basically adds up all of the individual instances processes and gives you a grand total for used memory in that instance alone.
This is sample output - yours may be different.
3

ps axo rss,comm | awk '{sum+=$1; print $1/1024, "MB - ", $2} END {print "\nTotal RAM Used: ", sum/1024, "MB\n"}'

johnss · 2010-02-18 12:05:45 7
Type a random string into a X11 window

Just after you type enter, you have 3 seconds to switch window, then "texthere" will be "typed" in the X11 application that has focus. Very useful to beat your score at games such as "How fast can you type A-Z".
This is sample output - yours may be different.
5

sleep 3 && xdotool type --delay 0ms texthere

drinkcat · 2010-02-18 11:44:18 20
List available upgrades from apt without upgrading the system
This is sample output - yours may be different.
3

apt-get --just-print upgrade

noqqe · 2010-02-18 11:19:05 8
Show top committers for SVN repositority for today
This is sample output - yours may be different.
6

svn log -r {`date "+%Y-%m-%d"`}:HEAD|grep '^r[0-9]' |cut -d\| -f2|sort|uniq -c

ivanatora · 2010-02-18 10:41:17 4
Averaging columns of numbers

Computes a columns average in a file. Input parameters = column number and optional pattern. Show Sample Output
This is sample output - yours may be different.
```
$> cat 0.5-10000.dat | avg 2 
Average over 10000 lines: 1.005299
```
0

function avg { awk "/$2/{sum += \$$1; lc += 1;} END {printf \"Average over %d lines: %f\n\", lc, sum/lc}"; }

vimzard · 2010-02-18 10:20:22 4
output your microphone to a remote computer's speaker
This is sample output - yours may be different.
32

arecord -f dat | ssh -C user@host aplay -f dat

drinkcat · 2010-02-18 06:00:33 25
How to install cron (crond, crontab)
This is sample output - yours may be different.
-15

yum install vixie-cron crontabs

svnlabs · 2010-02-17 16:36:10 6
Caching-Nameserver

Caching-Nameserver Show Sample Output
This is sample output - yours may be different.
```
install packages
yum -y install bind bind-chroot caching-nameserver

start service
service named restart

set autostart
chkconfig named on
```
-11

yum -y install bind bind-chroot caching-nameserver

svnlabs · 2010-02-17 16:35:06 3

RHEL / CentOS Support 4GB or more RAM ( memory )

RHEL / CentOS Support 4GB or more RAM ( memory ) Show Sample Output

-13

yum install kernel-PAE

svnlabs · 2010-02-17 16:34:09 4

How to Disable SELinux

just change SELINUX=enforcing to SELINUX=permissive, and you're done. Reboot if you want to prove it. Show Sample Output
This is sample output - yours may be different.
```
just change SELINUX=enforcing to SELINUX=permissive, and you're done. Reboot if you want to prove it.
```
-7

echo 0 >/selinux/enforce

svnlabs · 2010-02-17 16:33:26 3
View acceptable client certificate CA names asked for during SSL renegotiations

The key is to use the -prexit option at the command line, and then type "quit" instead of CTRL-C to exit OpenSSL. OpenSSL will then dump its last negotiated state, printing out the contents of the renegotiated handshake. Crucial for debugging client certificate configurations on web servers such as IIS, which renegotiate the SSL/TLS connection with the HTTP request in-flight to ask the client for a cert. Show Sample Output
This is sample output - yours may be different.
```
GET / HTTP/1.1
Host: www.example.com

read R BLOCK
HTTP/1.1 403 Forbidden

quit

---
Acceptable client certificate CA names
/C=US/O=YourOrg/OU=YourUnit/CN=YourCertificateAuthorityName1
/C=US/O=YourOrg/OU=YourUnit/CN=YourCertificateAuthorityName2
---
```
3

openssl s_client -connect www.example.com:443 -prexit

JonInVA · 2010-02-17 15:46:37 5
Provide a list of all ELF binary objects (executable or libs) in a directory

This is a dirty raw way to simply list ELF objects in a folder. The output is ready to be parsed i.e to the stripper or what else needs a path to an ELF object. Show Sample Output
This is sample output - yours may be different.
```
karmic@linux64:/home/karmic64/Test$ file /usr/bin/* | grep ELF | cut -d":" -f1 
/usr/bin/a2p
/usr/bin/aacplusenc
/usr/bin/aconnect
/usr/bin/acpi_fakekey
/usr/bin/acpi_listen
/usr/bin/addpart
/usr/bin/addr2line
/usr/bin/alsamixer
/usr/bin/amdcccle
/usr/bin/amidi
/usr/bin/amixer
/usr/bin/animate
/usr/bin/aplay
/usr/bin/aplaymidi
/usr/bin/appres
/usr/bin/apt-cache
```
-1

file /usr/bin/* | grep ELF | cut -d":" -f1

LucaCappelletti · 2010-02-17 14:01:52 3
Remote screenshot

The `export` is unnecessary if it's only applicable to the one command.
This is sample output - yours may be different.
18

DISPLAY=":0.0" import -window root screenshot.png

walterl · 2010-02-17 13:02:24 16
Remote Screenshot

Like the given command, but combines _DISPLAY=":0.0"_ with _export DISPLAY_ to get _export DISPLAY=":0.0"_ and only imports if DISPLAY is set successfully.
This is sample output - yours may be different.
-3

export DISPLAY=":0.0" && import -window root screenshot.png

fraktil · 2010-02-17 12:13:49 3
Count and show duplicate file names

Useful for C projects where header file names must be unique (e.g. when using autoconf/automake), or when diagnosing if the wrong header file is being used (due to dupe file names) Show Sample Output
This is sample output - yours may be different.
```
[user@localhost]$ find . -type f  |sed "s#.*/##g" |sort |uniq -c -d
      2 globals.h
      9 Makefile
      8 Makefile.bak
```
0

find . -type f |sed "s#.*/##g" |sort |uniq -c -d

shadycraig · 2010-02-17 11:59:54 5
diff recursively, ignoring CVS control files

This will cause diff to ignore any files whose path matches "*CVS*", ie any CVS control files.
This is sample output - yours may be different.
0

diff -x "*CVS*" -r <path-1> <path-2> [<path-3>]

sanmiguel · 2010-02-17 11:08:17 5
Introduction to user commands

Tested on debian and ubuntu. Translations could be useless, so "LANG=C man intro" is a better alternative.
This is sample output - yours may be different.
4

man intro

peppet · 2010-02-17 10:11:56 5
Allow any local (non-network) connection to running X server
This is sample output - yours may be different.
1

xhost +local:

peppet · 2010-02-17 09:20:39 3
Remote screenshot

Say if you're logged into a remote system via ssh and this system has an x window system, but yet you still want a screen shot of what's going on graphically. This will do it for you. :-)
This is sample output - yours may be different.
3

DISPLAY=":0.0"; export DISPLAY; import -window root gotya.png

Abiden · 2010-02-17 09:13:54 3
Google Spell Checker

I took matthewbauer's cool one-liner and rewrote it as a shell function that returns all the suggestions or outputs "OK" if it doesn't find anything wrong. It should work on ksh, zsh, and bash. Users that don't have tee can leave that part off like this: spellcheck(){ typeset y=$@;curl -sd "<spellrequest><text>$y</text></spellrequest>" https://google.com/tbproxy/spell|sed -n '/s="[1-9]"/{s/<[^>]*>/ /g;s/\t/ /g;s/ *$.*$/Suggestions: \1\n/g;p}';} Show Sample Output
This is sample output - yours may be different.
```
$ spellcheck motaive
Suggestions: motive motives mutative emotive motif

$ spellcheck now is the winter of our dicontent
Suggestions: discontent content contend

$ spellcheck panoply
OK
```
6

spellcheck(){ typeset y=$@;curl -sd "<spellrequest><text>$y</text></spellrequest>" https://www.google.com/tbproxy/spell|sed -n '/s="[0-9]"/{s/<[^>]*>/ /g;s/\t/ /g;s/ *$.*$/Suggestions: \1\n/g;p}'|tee >(grep -Eq '.*'||echo -e "OK");}

eightmillion · 2010-02-17 08:20:48 17
Google Spell Checker

http://immike.net/blog/2007/04/07/hacking-google-spell-checker-for-fun-and-profit/ Show Sample Output
This is sample output - yours may be different.
```
spell
```
1

spellcheck(){ curl -sd "<spellrequest><text>$1</text></spellrequest>" https://www.google.com/tbproxy/spell | sed 's/.*<spellresult [^>]*>$.*$<\/spellresult>/\1/;s/<c $[^>]*$>$[^<]*$<\/c>/\1;\2\n/g' | grep 's="1"' | sed 's/^.*;$[^\t]*$.*$/\1/'; }

matthewbauer · 2010-02-17 01:55:28 14
rename all jpg files with a prefix and a counter
This is sample output - yours may be different.
3

ls *.jpg | grep -n "" | sed 's,.*,0000&,' | sed 's,0*$...$:$.*$.jpg,mv "\2.jpg" "image-\1.jpg",' | sh

pepin · 2010-02-16 23:59:28 3
Get your commandlinefu points (upvotes - downvotes)

This version prints current votes and commands for a user. Pass the user as an argument. While this technically "fits" as a one liner, it really is easier to look at as a shell script with extra whitespace. :) Show Sample Output
This is sample output - yours may be different.
```
  0  sed 's/.*/ /'
  0  date -s "`curl -sI www.example.com | sed -n 's/^Date: //p'`"
  0  jot -s '' -b '-' 50
  7  command | sed -n '1,/regex/p'
  4  curl -s search.twitter.com | awk -F'</?[^>]+>' '/\/intra\/trend\//{print $2}'
  5  dig +short -x {ip}
```
2

curl -s http://www.commandlinefu.com/commands/by/$1/xml | awk -F'</?div[^>]*>' '/class=\"command\"/{gsub(/"/,"\"",$2); gsub(/</,"<",$2); gsub(/>/,">",$2); gsub(/&/,"\\&",$2); cmd=$2} /class=\"num-votes\"/{printf("%3i %s\n", $2, cmd)}'

putnamhill · 2010-02-16 17:24:45 5
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Google Spell Checker

I took matthewbauer's cool one-liner and rewrote it as a shell function that returns all the suggestions or outputs "OK" if it doesn't find anything wrong. It should work on ksh, zsh, and bash. Users that don't have tee can leave that part off like this: $spellcheck(){ typeset y=$@;curl -sd "$y" https://google.com/tbproxy/spell|sed -n '/s="[1-9]"/{s/]*>/ /g;s/\t/ /g;s/ *$.*$/Suggestions: \1\n/g;p}';}

Print all environment variables, including hidden ones

This uses some tricks I found while reading the bash man page to enumerate and display all the current environment variables, including those not listed by the 'env' command which according to the bash docs are more for internal use by BASH. The main trick is the way bash will list all environment variable names when performing expansion on ${!A*}. Then the eval builtin makes it work in a loop. I created a function for this and use it instead of env. (by aliasing env). This is the function that given any parameters lists the variables that start with it. So 'aae B' would list all env variables starting wit B. And 'aae {A..Z} {a..z}' would list all variables starting with any letter of the alphabet. And 'aae TERM' would list all variables starting with TERM. $ aae(){ local __a __i __z;for __a in "$@";do __z=\${!${__a}*};for __i in `eval echo "${__z}"`;do echo -e "$__i: ${!__i}";done;done; } And my printenv replacement is: $ alias env='aae {A..Z} {a..z} "_"|sort|cat -v 2>&1 | sed "s/\\^\\[/\\\\033/g"' From: http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

Tricky implementation of two-dimensional array in Bash.

Since Bash doesn't support two-dimensional arrays, you can limit your columns length by some big enough constant value ( in this example 100 ) and then index the array with i and j, or maybe write your own get() and set() methods to index the array properly like I implemented for example ( see Sample output ). For example for i=0 and j=0...99 you'll pick up one of 100 elements in the range [0,99] in the one-dimensional array. For i=1 and j=0...99 you'll pick up one of 100 elements in the range [100,199]. And so on. Be careful when using this, and remember that in fact you are always using one-dimensional array.

Basic sed usage with xargs to refactor a node.js depdendency

show dd progress

if you need see progress of long dd command, enter subj on other console

mysql bin log events per minute

shows number of mysql bin log events (which are mysql server events) per minute, useful to check stress times postmortem

Swap a file or dir with quick resotre

This lets you replace a file or directory and quickly revert if something goes wrong. For example, the current version of a website's files are in public_html. Put a new version of the site in public_html~ and execute the command. The names are swapped. If anything goes wrong, execute it again (up arrow or !!).

Create a bash script from last commands

In order to write bash-scripts, I often do the task manually to see how it works. I type ### at the start of my session. The function fetches the commands from the last occurrence of '###', excluding the function call. You could prefix this with a here-document to have a proper script-header. Delete some lines, add a few variables and a loop, and you're ready to go. This function could probably be much shorter...

Open Perl module source in your editor

Ever needed to look at the Perl source of an installed module on your system? This works in 90% of cases.

Get max number of arguments

Get max number of arguments that can be accepted by the exec() system call.

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