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Pick the first program found from a list of alternatives

This function is used to set environmental variables from a list of alternatives depending on what's installed on the system. It returns the first program found in the list. Example usage: export BROWSER=$(find_alternatives chromium-browser google-chrome opera firefox firefox-bin iceweasel konqueror w3m lynx) . export EDITOR=$(find_alternatives vim nano pico emacs kate) . export PAGER=$(find_alternatives vimpager less most more pg)
This is sample output - yours may be different.
-1

find_alternatives(){ for i;do which "$i" >/dev/null && { echo "$i"; return 0;};done;return 1;}

eightmillion · 2011-01-06 19:53:46 3
Remove superfluous from conf file

Use it with cat and '|' for know what is used in a conf file. For example cat /etc/squid/squid.conf | sed -re '/^#/d ; s/#.*$// ; /^\s$/d' : Show you what you use in your file conf. It removes all comments and empty lines. Empty lines are lines with nothing, a tab, or a space.
This is sample output - yours may be different.
-1

sed -re '/^#/d ; s/#.*$// ; /^\s*$/d'

Zulu · 2012-02-02 18:12:52 4
Create random password in reasonable time

It will produce passwords with length of 20 printable characters within a reasonable time. For shorter or longer passwords just change the 20 in bs=20 to something more convenient. To create only alpha numeric passwords change [:print:] to [:alnum:] Show Sample Output
This is sample output - yours may be different.
```
$ dd if=/dev/urandom  | tr -d -c [:print:] | tr -d " " | dd count=1 bs=20  2> /dev/null; echo 
beO+Y`gS%rbAFNH`qd/?
```
-1

dd if=/dev/urandom | tr -d -c [:print:] | tr -d " " | dd count=1 bs=20 2> /dev/null; echo

Progent · 2013-03-01 22:42:29 5
removing those pesky malformed lines at the end of a text file..

tells you the number of lines in said file, and then tail the last 100 lines ( or how many are messed up) then u take the total amount of lines and then subract the 100 or so lines u DONT WANT, then do a head -n $new_number and then redirect it to new file.db
This is sample output - yours may be different.
-1

cat -n $file | tail -n 100 && head -n number-of-lines-you-want-to-keep > newfile

bbelt16ag · 2009-02-15 01:02:10 9
Check the backdoors and security.chkrootkit is a tool to locally check for signs of a rootkit.

chkrootkit is a tool to locally check for signs of a rootkit,Get it from the website http://www.chkrootkit.org
This is sample output - yours may be different.
-1

chkrootkit -x | less

unixbhaskar · 2009-08-30 12:47:08 3
to display number of lines in a file without using wc command
This is sample output - yours may be different.
-1

sed -n "$=" fileName

harish · 2010-10-19 08:50:24 3
convert myisam to innodb

Convert all Tables from MyISAM to InnoDB
This is sample output - yours may be different.
-1

for I in $(echo "show tables" | mysql -u<user> <database>`; do echo "ALTER TABLE $I ENGINE = INNODB"| mysql -u<user> <database>; done

int9h · 2011-12-16 14:51:10 15
which domain controller the user currently logged onto

The command line can be accessed by using the cmd command which will open a command window with a DOS interface. The command line is a throw back to the early days of computing before there was a Windows interface. Show Sample Output
This is sample output - yours may be different.
```
\\cicciobombadc
```
-1

echo %logonserver%

0disse0 · 2011-06-13 09:52:51 6
List of commands you use most often

List of commands you use most often suppressing sudo Show Sample Output
This is sample output - yours may be different.
```
64 ifconfig
35 firefox
33 ls
29 ping
28 yaourt
27 history
25 cat
21 vim
19 /etc/rc.d/wireless
17 init
```
-1

history | awk '{if ($2 == "sudo") a[$3]++; else a[$2]++}END{for(i in a){print a[i] " " i}}' | sort -rn | head

JamieKitson · 2012-12-31 13:45:03 4
HDD Performance Read Test

Test your XFS filesystem and Raptor hard drives for write performance.
This is sample output - yours may be different.
-1

dd if=10gb of=/dev/zero bs=1M count=10240

logik · 2009-02-18 15:30:29 10
See The MAN page for the last command
This is sample output - yours may be different.
-1

man !!

SQUIIDUX · 2010-08-14 14:09:31 3
Show amigable path

change ":" in path for new line and associate word path to var $PATH
This is sample output - yours may be different.
-1

alias path='echo $PATH | tr ":" "\n"'

voyeg3r · 2009-03-12 17:07:58 5
use ImageMagik to convert tint (hue rotation) of an icon set directory.
This is sample output - yours may be different.
-1

mogrify -modulate 100,100,70 ../../icons/32x32/*.png

houghi · 2011-06-13 15:11:16 3
Batch resize all images to a width of 'X' pixels while maintaing the aspect ratio

Batch resize all images to a width of 'X' pixels while maintaing the aspect ratio. This makes uses of ImageMagick to make life easier.
This is sample output - yours may be different.
-1

mogrify -resize SIZE_IN_PIXELS *.jpg

o0110o · 2013-07-05 14:14:04 6
Edit a single line in multiple files with sed

Find and replace specific characters in a single line in multiple files with sed. Show Sample Output
This is sample output - yours may be different.
```
Original file
file1.txt:This is the MATCHING STRING and ORIGINAL some more text

Replaced file

file1.txt:This is the MATCHING STRING and REPLACEMENT some more text
```
-1

for f in `ls`; do sed -i '/MATCHING STRING/ { s/ORIGINAL/REPLACEMENT/; }' ${f} ; done

krizzo · 2015-05-21 19:37:42 15
remove the last line of all html files in a directory

Some malicious program appends a iframe or script tag to you web pages on some server, use this command to clean them in batch.
This is sample output - yours may be different.
-1

for f in *.html; do head -n -1 $f > temp; cat temp > $f; rm temp; done

Sunng · 2009-10-12 12:49:18 5
How To Get the Apache Document Root
This is sample output - yours may be different.
-1

grep -i '^DocumentRoot' /etc/httpd/conf/httpd.conf | cut -f2 -d'"'

hm2k · 2010-07-14 13:30:36 3
Sort a list of numbers on on line, separated by spaces.

You can replace "sort -nu" with "sort -u" for a word list sorted or "sort -R" for a random-sorted line (edit: corrected) Show Sample Output
This is sample output - yours may be different.
```
$ echo "4 2  3 5  2 52  11" | sed "s/$ \|$$/\n/g" | sort -nu | tr "\n" " "| sed -e "s/^ *//" -e "s/ $//"
2 3 4 5 11 52
```
-1

echo $numbers | sed "s/$ \|$$/\n/g" | sort -nu | tr "\n" " " | sed -e "s/^ *//" -e "s/ $//"

chickenzilla · 2009-06-24 15:12:17 7
Selecting a random file/folder of a folder

Here's a bash version using an array.
This is sample output - yours may be different.
-1

a=(*); echo ${a[$((RANDOM % ${#a[@]}))]}

putnamhill · 2011-03-18 13:24:52 3

This is sample output - yours may be different.

view this page source to copy perl command.

====================
== make alias

$ cat alias.txt # this line is too long to post Command-line-fu
perl -MHTML::Form -MLWP::UserAgent -e'$a=LWP::UserAgent->new;push@{$a->{requests_redirectable}},"POST";$u="http://www.commandlinefu.com/commands/browse";$f=HTML::Form->parse($a->get($u)->content,$u);$f->value(q=>join" ",@ARGV);for($a->request($f->click)->content=~m!<div class="one-liner">(.+?)(?=<div class="one-liner">|</html>)!sg){($s)=m!<div class="summary".+?>(.+?)<!s;($_)=m!<div class="command">\s*(.*?)<!s;s/</</g;s/>/>/g;s/"/"/g;s/&/&/g;print"### $s\n$_\n\n";++$n>7&&last}'

$ alias clgrep=`cat alias.txt`

====================
== grep the archive about "backup"

$ clgrep backup
### quickly backup or copy a file with bash
cp filename{,.bak}

### infile search and replace on N files (including backup of the files)
perl -pi.bk -e's/foo/bar/g' file1 file2 fileN

### backup directory. (for bash)
cp -pr directory-you-want-to-backup{,_`date +%Y%m%d`} # for bash

$ 

====================
== grep the archive about "wget"

$ clgrep wget
### Download all images from a site
wget -r -l1 --no-parent -nH -nd -P/tmp -A".gif,.jpg" http://example.com/images

### Extract tarball from internet without local saving
wget -qO - "http://www.tarball.com/tarball.gz" | tar zxvf -

### Echo the latest commands from commandlinefu on the console
wget -O - http://www.commandlinefu.com/commands/browse/rss 2>/dev/null | awk '/\s*<title/ {z=match($0, /CDATA\[([^\]]*)\]/, b);print b[1]} /\s*<description/ {c=match($0, /code>(.*)<\/code>/, d);print d[1]"\n"} '

### Get My Public IP Address
wget -qO - http://myip.dk/ | egrep -m1 -o '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}'

$


====================
== grep recently posted

$ clgrep 
### Launch an Explorer window with a file selected
explorer /select,[file]

### Search specified $TEXT1 and Replace that by specified arg ($TEXT2)
find "$DIR" -regex "$FILENAME" -type f -print0 | xargs -0 sed -i _`date "+%y%m%d%H%M%S"` -E "s/$TEXT1/$TEXT2/g"

### count IPv4 connections per IP
netstat -anp |grep 'tcp\|udp' | awk '{print $5}' | sed s/::ffff:// | cut -d: -f1 | sort | uniq -c | sort -n

$

-1

clgrep keyword

wbx · 2009-02-15 11:45:28 10

simulates the DOS tree command that you might be missing on your Mac or Linux box

NOT MINE! Taken from hackzine.com blog. It creates a tree-style output of all the (sub)folders and (sub)files from the current folder and down(deeper) Quoting some of hackzine's words "Murphy Mac sent us a link to a handy find/sed command that simulates the DOS tree command that you might be missing on your Mac or Linux box. [..split...] Like most things I've seen sed do, it does quite a bit in a single line of code and is completely impossible to read. Sure it's just a couple of substitutions, but like a jack in the box, it remains a surprise every time I run it." Show Sample Output
This is sample output - yours may be different.
```
$ cd amsn_received
$ find . -print | sed -e 's;[^/]*/;|____;g;s;____|; |;g'
.
|____amsn_received
| |____screenshot1.png
| |____DSCF1171.JPG
| |____DSCF1202.JPG
| |____DSC00887.jpg
| |____DSC00953.jpg
| |____DSC00595.JPG
| |____at92A3.tmp.jpg
| |____ReadMe 1.pdf
| |____Screenshot.png
| |____cpuz.html
```
-1

find . -print | sed -e 's;[^/]*/;|____;g;s;____|; |;g'

JesusSuperstar · 2009-03-12 22:25:26 8
Get list of all Apache Virtual Host and which is default for each IP address

Show Sample Output
This is sample output - yours may be different.
```
VirtualHost configuration:
1.2.3.4:80     is a NameVirtualHost
         default server domain.com (/etc/httpd/conf.d/domain_virhost.conf:1)
         port 80 namevhost domain.com (/etc/httpd/conf.d/domain_virhost.conf:1)
Syntax OK
```
-1

httpd -S

flip387 · 2009-08-30 15:28:39 4
Find the uid and gid of your apache process

This command allows you to find the effective uid and gid of the Apache process regardless of process name (which can be apache2 or httpd depending on distro).
This is sample output - yours may be different.
-1

ps -o euid,egid --ppid `netstat --inet --inet6 -pln|awk '/:80 / { split($7,tmp, "/"); print tmp[1]; }'`|sort |uniq|grep -v EUID

chx · 2010-11-18 21:22:29 2

List debian package installed by size

You need to install the package wajig. Show Sample Output

-1

wajig large

log0 · 2009-09-16 22:14:27 3

use vim to get colorful diff output
This is sample output - yours may be different.
-1

vimdiff file1 file2

slappy · 2012-08-24 14:58:37 4
‹ First < 490 491 492 493 494 > Last ›

What's this?

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Welcome humans!

Some information about robots. :-)

Print only the odd lines of a file

NR%2 == 1 on odd lines and 0 on even lines

list block devices

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

Comment out a line in a file

This will comment out a line, specified by line number, in a given file.

Use xdg-open to avoid hard coding browser commands

I rarely use the system menu to start applications. I use keyboard shortcuts instead. Keyboard shortcuts are convenient time savers. To configure the shortcuts I use gconf-editor or CompizConfig Settings Manager (if I have Compiz turned on). Lately I've been using Chromium as my browser. Since Chromium is under heavy development it occasionally becomes unusable and I have to switch back to Firefox. I was hard-coding the browser command in my keyboard shortcuts. This became problematic with frequent browser hopping. I now use the xdg-open command when defining my keyboard shortcuts. xdg-open opens a file or URL in the user's preferred application. In the metacity keybinging_commands I have xdg-open http://gmail.com where I used to have firefox http://gmail.com. Now when switching browsers I don't have to update each keyboard binding command I just change my default browser in Ubuntu by clicking through the menu: System / Preferences / Preferred Applications / Web Browser. xdg-open is more convenient for this browser hopper.

list all opened ports on host

nmap get all active online ips from specific network

scan whole specific network for active online ips

Get and read log from remote host (works with log on pipe, too)

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)

Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

Super Speedy Hexadecimal or Octal Calculations and Conversions to Decimal.

^Hexadecimal Ten minus Octal Ten is Eight(in Decimal). $ echo "$(( 0xaf )) = $(( 0257 ))" ^Hexadecimal AF and Octal 257 are both Decimal 175.

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