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force change password for all user

This assumes that te original's 'passwd -e' forces a user to change password; it doesn't in the versions I have.
This is sample output - yours may be different.
0

while IFS=: read u x; do passwd -e "$u"; done < /etc/passwd

cfajohnson · 2009-11-20 21:49:34 7
Find all dot files and directories
This is sample output - yours may be different.
1

printf "%s\n" .*

cfajohnson · 2009-11-20 21:41:02 3
Show sorted list of files with sizes more than 1MB in the current dir
This is sample output - yours may be different.
1

ls -l | awk '$5 > 1000000' | sort -k5n

cfajohnson · 2009-11-20 21:18:45 7
remove files and directories with acces time older than a given time

Deletes files older than "n" minutes ago. Note the plus sign before the n is important and means "greater than n". This is more precise than atime, since atime is specified in units of days. NOTE that you can use amin/atime, mmin/mtime, and cmin/ctime for access, modification, and change times, respectively. Also, using -delete is faster than piping to xargs, since no piping is needed.
This is sample output - yours may be different.
-1

find -amin +[n] -delete

TeacherTiger · 2009-11-20 17:15:28 4
Show sorted list of files with sizes more than 1MB in the current dir

no fancy grep stuff here.
This is sample output - yours may be different.
2

du | sort -nr | cut -f2- | xargs du -hs

unixmonkey7118 · 2009-11-20 17:14:40 4
remove files and directories with acces time older than a given date

remove files with access time older than a given date. If you want to remove files with a given modification time replace %A@ with %T@. Use %C@ for the modification time. The time is expressed in epoc but is easy to use any other format. Show Sample Output
This is sample output - yours may be different.
```
~/tmp$ find . -printf '%p : %A@\n' | awk '{FS=" : " ; if($2 < 1258734167 ) print $1 ;}' | xargs rm --verbose -fr ;
removed `./file_1'
removed `./file_2'
removed `./file_3'
removed `./file_4'
removed `./file_5'
removed `./file_6'
removed `./file_7'
removed `./file_8'
removed `./file_9'
```
-2

find <dir> -printf '%p : %A@\n' | awk '{FS=" : " ; if($2 < <time in epoc> ) print $1 ;}' | xargs rm --verbose -fr ;

angleto · 2009-11-20 16:31:58 9
exit if another instance is running

runs only one instance.
This is sample output - yours may be different.
2

if [ `fuser $0|wc -w` -gt "1" ];then exit; fi

yooreck · 2009-11-20 16:22:30 5

Plot frequency distribution of words from files on a terminal.

Uses the dumb terminal option in gnuplot to plot a graph of frequencies. In this case, we are looking at a frequency analysis of words in all of the .c files. Show Sample Output

This is sample output - yours may be different.

$ cat *.c | { printf "se te du\nplot '-' t '' w dots\n"; tr '[[:upper:]]' '[[:lower:]]' | tr -s [[:punct:][:space:]] '\n' | sort | uniq -c | sort -nr | head -n 100 | awk '{print $1}END{print "e"}'; } | gnuplot

  60 .+-----+------+------+------+-------+------+------+------+------+-----++
     +      +      +      +      +       +      +      +      +      +      +
     |                                                                      |
  50 ++                                                                    ++
     |                                                                      |
     |.                                                                     |
     |.                                                                     |
  40 ++                                                                    ++
     |                                                                      |
     | ..                                                                   |
  30 ++                                                                    ++
     |   .                                                                  |
     |                                                                      |
  20 ++  ..                                                                ++
     |     ..                                                               |
     |       ..                                                             |
     |         ...                                                          |
  10 ++           ....                                                     ++
     |                ...............                                       |
     +      +      +      +      +   .......................................+
   0 ++-----+------+------+------+-------+------+------+------+------+-----++
     0      10     20     30     40      50     60     70     80     90    100

cat *.c | { printf "se te du\nplot '-' t '' w dots\n"; tr '[[:upper:]]' '[[:lower:]]' | tr -s [[:punct:][:space:]] '\n' | sort | uniq -c | sort -nr | head -n 100 | awk '{print $1}END{print "e"}'; } | gnuplot

taliver · 2009-11-20 14:53:26 7

Short Information about loaded kernel modules
This is sample output - yours may be different.
4

awk '{print $1}' "/proc/modules" | xargs modinfo | awk '/^(filename|desc|depends)/'

unixmonkey7109 · 2009-11-20 13:06:25 3
exit if another instance is running
This is sample output - yours may be different.
8

pidof -x -o $$ ${0##*/} && exit

frans · 2009-11-20 12:58:41 6
Remove an unnecessary suffix from a file name for all files in a directory

For this example, all files in the current directory that end in '.xml.skippy' will have the '.skippy' removed from their names.
This is sample output - yours may be different.
-2

for f in $(ls *.xml.skippy); do mv $f `echo $f | sed 's|.skippy||'`; done

argherna · 2009-11-19 21:36:26 20
Write and run a quick C program

This is a quick hack to make a gcc caller. Since it runs with gcc instead of tcc, it's a bit more trustworthy as far as the final answers of things go. Show Sample Output
This is sample output - yours may be different.
```
$ cat ~/.stdin.c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <utmp.h>
#include <errno.h>

int main(int argc, char *argv[]) {
  #include "/dev/tty"
  return 0;
}

$ cstdin
Ctrl-D when done.
printf("Size of an unsigned long long is %lu\n", sizeof (unsigned long long));
Size of an unsigned long long is 8
```
-3

alias cstdin='echo "Ctrl-D when done." && gcc -Wall -o ~/.stdin.exe ~/.stdin.c && ~/.stdin.exe'

taliver · 2009-11-19 16:38:51 4
Remove an IP address ban that has been errantly blacklisted by denyhosts

download the denyhosts-remove script from http://www.atrixnet.com/remove-an-ip-address-ban-that-has-been-errantly-blacklisted-by-denyhosts/
This is sample output - yours may be different.
2

denyhosts-remove $IP_ADDRESS

linuxrawkstar · 2009-11-19 16:28:34 10
Random password generating function

This uses urandom to produce a random password. The random values are uuencoded to ensure only printable characters. This only works for a number of characters between 1 and 60. Show Sample Output
This is sample output - yours may be different.
```
$ mkpasswd 56
AB:C[)\"=H#J:E()EY>HA6J,R741+ACL&08PC)P4Z#3R^YZ*3L0@O<<6
$ mkpasswd 9
YMO;<&.FB
```
-3

mkpasswd() { head -c $(($1)) /dev/urandom | uuencode - | sed -n 's/.//;2s/$.\{'$1'\}$.*/\1/p' ;}

taliver · 2009-11-19 14:27:52 5

Simple read and write test with Iozone

Iozone with a file of 2GB, 64KB record size, write/rewrite and read/re-read test, using just one thread. Show Sample Output

iozone -s 2g -r 64 -i 0 -i 1 -t 1

w00binda · 2009-11-19 10:43:54 3

Testing reading speed with dd
This is sample output - yours may be different.
1

sync; time `dd if=/dev/cciss/c0d1p1 of=/dev/null bs=1M count=10240`

w00binda · 2009-11-19 10:34:13 3
Testing writing speed with dd
This is sample output - yours may be different.
0

sync; time `dd if=/dev/zero of=bigfile bs=1M count=2048 && sync`

w00binda · 2009-11-19 10:29:03 13
Script to rip the audio from the youtube video you have open in firefox

Must have the video open and fully loaded.
This is sample output - yours may be different.
-2

video=$(ls /tmp | grep -e Flash\w*); ffmpeg -i /tmp/$video -f mp3 -ab 192k ~/ytaudio.mp3

aperson · 2009-11-19 09:25:10 8
github push-ing behind draconian proxies!

If you are behind a restrictive proxy/firewall that blocks port 22 connections but allows SSL on 443 (like most do) then you can still push changes to your github repository. Your .ssh/config file should contain: Host * ForwardX11 no TCPKeepAlive yes ProtocolKeepAlives 30 ProxyCommand /usr/local/bin/proxytunnel -v -p -d %h:443 Host User git Hostname ssh.github.com ChallengeResponseAuthentication yes IdentityFile ~/.ssh/id_rsa IdentitiesOnly yes Basically proxytunnel "tunnels" your ssh connection through port 443. You could also use corkscrew or some other tunneling program that is available in your distro's repository. PS: I generally use "github.com" as the SSH-HOST so that urls of the kind git@github.com:USER/REPO.git work transparently :) You
This is sample output - yours may be different.
3

git remote add origin git@SSH-HOST:<USER>/<REPOSITORY>.git

jnash · 2009-11-19 06:57:50 8
Better "hours of video" summary for each file/dir in the current directory

I know this has been beaten to death but finding video files using mime types and printing the "hours of video" for each directory is (IMHO) easier to parse than just a single total. Output is in minutes. Among the other niceties is that it omits printing of non-video files/folders PS: Barely managed to fit it within the 255 character limit :D Show Sample Output
This is sample output - yours may be different.
```
Fundamentals Of Physics - 1724.32
Google Techtalks - 258.292
Introduction to Algorithms - 1805.26
Linear Algebra - 1675.23
```
0

for item in *;do echo -n "$item - ";find "$item" -type f -print0 | xargs -0 file -iNf - | grep video | cut -d: -f1 | xargs -d'\n' /usr/share/doc/mplayer/examples/midentify | grep ID_LENGTH | awk -F= '{sum+=$2} END {print(sum/60)}'; done | grep -v ' - 0$'

jnash · 2009-11-19 06:28:15 3
Find all videos under current directory

Uses mime-type of files rather than relying on file extensions to find files of a certain type. This can obviously be extended to finding files of any other type as well.. like plain text files, audio, etc.. In reference to displaying the total hours of video (which was earlier posted in command line fu, but relied on the user having to supply all possible video file formats) we can now do better: find ./ -type f -print0 | xargs -0 file -iNf - | grep video | cut -d: -f1 | xargs -d'\n' /usr/share/doc/mplayer/examples/midentify | grep ID_LENGTH | awk -F "=" '{sum += $2} END {print sum/60/60; print "hours"}'
This is sample output - yours may be different.
1

find ./ -type f -print0 | xargs -0 file -iNf - | grep video | cut -d: -f1

jnash · 2009-11-19 06:05:36 6
Short Information about loaded kernel modules

I modify 4077 and marssi commandline to simplify it and skip an error when parsing the first line of lsmod (4077). Also, it's more concise and small now. I skip using xargs ( not required here ). This is only for GNU sed. For thoses without GNU sed, use that : modinfo $(lsmod | awk 'NR>1 {print $1}') | sed -e '/^dep/s/$/\n/g' -e '/^file/b' -e '/^desc/b' -e '/^dep/b' -e d
This is sample output - yours may be different.
6

modinfo $(cut -d' ' -f1 /proc/modules) | sed '/^dep/s/$/\n/; /^file\|^desc\|^dep/!d'

sputnick · 2009-11-18 23:40:46 4
force change password for all user

Alternately for those without getent or only want to work on local users it's even easier: cut -d: -f1 /etc/passwd|xargs -n1 passwd -e Note that not all implementations of passwd support -e. On RH it would be passwd -x0 (?) and on Solaris it would be passwd -f.
This is sample output - yours may be different.
0

getent passwd|cut -d: -f1|xargs -n1 passwd -e

romulusnr · 2009-11-18 19:46:15 11
View the latest astronomy picture of the day from NASA.

Substitute feh for the image viewer of your choice. display (part of imagemagick) seems to be a popular choice.
This is sample output - yours may be different.
3

apod(){ local x=http://antwrp.gsfc.nasa.gov/apod/;feh $x$(curl -s ${x}astropix.html|grep -Pom1 'image/\d+/.*\.\w+');}

eightmillion · 2009-11-18 12:06:03 8
rotate the compiz cube via command line

0-1279 = desktop 1 region = face 1 1280-2559 = face 2 ==>> wmctrl 1280 = wmctrl (1281,...2559) are all the same for a 1280 monitor resolution math: argument of wmctrl -o = ( DesiredFace * HorizontalResolution - 1)
This is sample output - yours may be different.
1

wmctrl -o 1280,0

m33600 · 2009-11-18 11:06:29 31
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Print a cron formatted time for 2 minutes in the future (for crontab testing)

Another function to stick into your .bashrc This spits out the time two minutes in the future, but already formatted for pasting into your crontab file for testing without any thought required on your part. Frequently things don't work the way you expect inside a crontab job, and you probably want to find out now that your $PATH is completely different inside of cron or other global variables aren't defined. So this will generate a date you can use for testing now, and then later you can change it to run at 5:37 am on a Sunday evening.

To Stop or Start (Restart) a Windows service from a Linux machine

intercept stdout/stderr of another process or disowned process

Useful to recover a output(stdout and stderr) "disown"ed or "nohup"ep process of other instance of ssh. With the others options the stdout / stderr is intercepted, but only the first n chars. This way we can recover ALL text of stdout or stderr

Search for a string inside all files in the current directory

This is how I typically grep. -R recurse into subdirectories, -n show line numbers of matches, -i ignore case, -s suppress "doesn't exist" and "can't read" messages, -I ignore binary files (technically, process them as having no matches, important for showing inverted results with -v) I have grep aliased to "grep --color=auto" as well, but that's a matter of formatting not function.

add all files not under version control to repository

With the force options the same results can be achieved

ffmpeg command that transcodes a MythTV recording for Google Nexus One mobile phone

This command will transcode a MythTV recording. The target device is a Google Nexus One mobile phone. My recordings are from a HDHomerun with Over The Air content. Plays back nicely on the N1.

Take aWebcam Picture When the Mouse Moves

This takes a webcam picture every everytime the mouse is moved (waits 10 seconds between checking for movement) and stores the picture wherever you want it. Ideas: Use in conjunction with a dropbox type application to see who is using your computer Use /dev/input/mice if /dev/input/mouse* doesn't work Use the bones of this to make a simple screensaver

list block devices

Shows all block devices in a tree with descruptions of what they are.

find and delete files smaller than specific size

Show a curses based menu selector

Not so much handy by itself, but very nice in shell scripts. This makes you a handy ncurses based checklist. Much like terminal installers, just use the arrow keys and hit 'Space' to adjust the selections. Returns all selected tags as strings, with no newline at the end. So, your output will be something like: "one" "two" "three" "four" "etc" For those who prefer bash expansion over gratuitious typing: $ whiptail --checklist "Simple checkbox menu" 12 35 3 $(echo {one,two,three,four}" '' 0"} ) Things to note: The height must includes the outer border and padding: add 7 to however many items you want to show up at the same time. If the status is 1, it will be selected by default. anything else, will be deselected.

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