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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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Generate random passwords (from which you may select "memorable" ones)

See: "man pwgen" for full details. Some Linux distros may not have pwgen included in the base distribution so you maye have to install it (eg in Mandriva Linux: "urpmi pwgen").

Send data securly over the net.

Using OpenSSL we can encrypt any input we wish and then use Netcat to create a socket which can be connected to from an externally source (even using a Web Browser)

Countdown Clock

Simple countdown clock that should be quite portable across any Bourne-compatible shell. I used to teach for a living, and I would run this code when it was time for a break. Usually, I would set "MIN" to 15 for a 15-minute break. The computer would be connected to a projector, so this would be projected on screen, front and center, for all to see.

delete duplicate lines from a file and keep the order of the other lines

i wanted to delete all duplicate lines from .bash_history and keep the order of the other lines. the command cat's the file and adds line numbers, then sorts by the second column. afterwards uniq omits repeated lines, but skips the first field (the line number). then it sorts by the line numbers and at the end cuts the numbers off.

Analyze awk fields

translate and number lines is simpler and you use tr to choose your delimiter (eg for csv files)

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

Speed up launch of liferea

If you use liferea frequently, you will see obvious speedup after you executed this command.

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Binary digits Matrix effect

Silly Perl variant.

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.

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