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Commands using cat

Commands using cat from sorted by
Terminal - Commands using cat - 380 results
whois -H $(cat ./list_of_domains) | awk 'BEGIN{RS=""}/Registrant/,/Registration Service Provider:/ {print} END{print "----------------\n"}'
2011-01-11 12:55:34
User: djsmiley2k
Functions: awk cat whois
0
Up
Down
List contact infomation for Domain list

Nice neat feedback showing contact infomation for as many domains as you wish to feed it. I used a list of domains, each one on a new line as supplied by our registar, as we needed to check they were all upto date and back them up as we are updating them all.

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cat /dev/urandom | hexdump -C | highlight ca fe 3d 42 e1 b3 ae f8 | perl -MTime::HiRes -pne "Time::HiRes::usleep(rand()*1000000)"
2010-12-29 21:26:18
User: doherty
Functions: cat hexdump perl
Tags: bash perl hexdump random highlight
1
Up
Down
shell equivalent of a boss button

Nobody wants the boss to notice when you're slacking off. This will fill your shell with random data, parts of it highlighted. Note that 'highlight' is the Perl module App::highlight, not "a universal sourcecode to formatted text converter." You'll also need Term::ANSIColor.

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head -100000 /dev/urandom | strings > temp.txt && for w in $(cat webster-dictionary.txt); do if [ ${#w} -gt 3 ]; then grep -io $w temp.txt; fi; done
2010-12-23 01:58:56
User: rugina
Functions: cat grep head strings
6
Up
Down
Look for English words in /dev/urandom

* to get the English dictionary: wget http://www.mavi1.org/web_security/wordlists/webster-dictionary.txt

Show sample output | Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat file | tr -d "\n"
2010-12-02 09:22:02
User: uzsolt
Functions: cat file tr
Tags: Text Processing
-1
Up
Down
Join lines

This command deletes the "newline" chars, so its output maybe unusable :)

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cat file | tr "\n" " "
2010-12-02 09:21:02
User: uzsolt
Functions: cat file tr
Tags: Text Processing
8
Up
Down
Join lines

It's works only when you replace '\n' to ONE character.

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cat video.ogg | nc -l -p 4232 & wget http://users.bshellz.net/~bazza/?nombre=name -O - & sleep 10; mplayer http://users.bshellz.net/~bazza/datos/name.ogg
2010-11-29 03:34:31
User: el_bazza
Functions: cat sleep wget
Tags: video audio ogg mplayer stream streaming vorbis Videos webcam vlc theora
-1
Up
Down
Send and streamming video to web

Is a simple script for video streaming a movie

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cat /etc/services | egrep [[:blank:]]<port_number>/
2010-11-25 08:04:31
User: xutale
Functions: cat egrep
0
Up
Down
Find which service was used by which port number

Apply to almost linux distroes.

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ls | grep .gz >> list.txt && cat list.txt | while read x ; do gunzip -d $x ; done && rm -rf list.txt
2010-11-17 11:06:02
User: maccu
Functions: cat grep gunzip ls read rm
-10
Up
Down
gunzip all .gz file in current dir

gunzip all .gz file in current dir

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pcharc(){ perl -e 'for (0..255) {$_ = chr($_); print if /['$1']/}' | cat -v; echo;}
2010-11-13 00:32:41
User: putnamhill
Functions: cat perl
Tags: perl
1
Up
Down
print character classes

Today I needed a way to print various character classes to use as input for a program I was writing. Also a nice way to visualize character classes.

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat index.html | sed 's|"index.html%3Ffeed=rss2"|"http://dynamic-blog.hemca.com/?feed=rss2.html"|g'
2010-11-05 20:27:21
User: strzel_a
Functions: cat sed
2
Up
Down
Complex string encoding with sed

Pipe | avoid escaping occurences problems in using sed and make it easier to use

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cat file.txt | sed -e /<opening tag>/d -e /<closing tag>/G | sed -e '/./{H;$!d;}' -e 'x;/<string to search>/!d;'
2010-11-04 10:31:15
User: EBAH
Functions: cat sed
Tags: grep tag filter multiline
2
Up
Down
Multi line grep using sed and specifying open/close tags

Working with log files that contains variable length messages wrapped between open and close tags it may be useful to filter the messages upon a keyword.

This works fine with GNU sed version 4.2 or higher, so pay attention to some unix distros (solaris, hp-ux, etc.).

Linux should be ok.

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ps -u $USER -lf | grep -vE "\-bash|sshd|ps|grep|PPID" > .tmpkill; if (( $(cat .tmpkill | wc -l) > 0 )); then echo "# KILL EM ALL"; cat .tmpkill; cat .tmpkill | awk '{print $4}' | xargs kill -9; else echo "# NOTHING TO KILL"; fi; cat .tmpkill; rm .tmpkill;
2010-11-04 04:16:50
User: zsugiart
Functions: awk cat echo grep kill ps rm wc xargs
0
Up
Down
kill all process that belongs to you

Kills all process that belongs to the user that runs it - excluding bash, sshd (so putty/ssh session will be spared). The bit that says grep -vE "..." can be extended to include ps line patterns that you want to spare.

If no process can be found on the hitlist, it will print # NOTHING TO KILL. Otherwise, it will print # KILL EM ALL, with the cull list.

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for _a in {A..Z} {a..z};do _z=\${!${_a}*};for _i in `eval echo "${_z}"`;do echo -e "$_i: ${!_i}";done;done|cat -Tsv
2010-10-27 07:16:54
User: AskApache
Functions: cat echo
Tags: cat bash sort sed echo alias function print for builtin askapache do variable for loop env environment printenv done
1
Up
Down
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

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cat /proc/version
2010-10-20 15:56:10
User: unixmonkey13150
Functions: cat
0
Up
Down
Find out my Linux distribution name and version
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
cat /etc/*-release
2010-10-20 15:03:39
User: frank514
Functions: cat
1
Up
Down
Find out my Linux distribution name and version
Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
diff <(ssh user@host1 cat /path/to/file) <(ssh user@host2 cat /path/to/file2)
2010-10-13 11:15:38
User: auxten
Functions: cat diff ssh
1
Up
Down
diff 2 remote files
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cat > /dev/null
2010-10-08 14:35:25
User: GouNiNi
Functions: cat
Tags: screen key sequence
-5
Up
Down
Get non-printable keycode to bind keys in applications

In exemple, screen can bind keys to switch between windows. I like to use Ctrl + Arrow to move left or right window. So I bind like this in .screenrc :

bindkey ^[OD prev # Ctl-left, prev window

bindkey ^[OC next # Ctl-right, next window

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cat dvd_output/Layer0/IMAGE.DAT dvd_output/Layer1/IMAGE.DAT > dvd.iso
2010-10-07 18:47:39
User: clintmiller
Functions: cat
Tags: testing dvd burning
0
Up
Down
Combine DVD Studio Pro DDP layers back into a DVD disc image for testing

This will you combine the DDP output of DVD Studio Pro back into a standard ISO disk image so that you can double-check the DDP output process.

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export GREP_COLOR='1;32'; cat /dev/urandom | hexdump -C | grep --color=auto "ca fe"
2010-10-04 18:08:11
User: zzambia
Functions: cat export grep hexdump
4
Up
Down
pretend to be busy in office to enjoy a cup of coffee
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cat /dev/urandom | hexdump -C | grep "ca fe"
2010-09-27 08:20:44
User: BOYPT
Functions: cat grep hexdump
26
Up
Down
pretend to be busy in office to enjoy a cup of coffee

just make some data scrolling off the terminal. wow.

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cat /proc/cpuinfo
2010-09-24 09:27:58
User: magicjohnson_
Functions: cat
Tags: bash cpuinfo
-1
Up
Down
CPU architecture details

It works in every linux box

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ps -a |grep cat |wc -l
2010-09-22 23:57:19
User: schmiddim
Functions: cat grep ps wc
-2
Up
Down
count how many cat processes are running
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pdftk input.pdf cat 1-endE output output.pdf
2010-09-21 20:10:23
User: juanan
Functions: cat
1
Up
Down
Rotate a pdf by 90 degrees CW
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package=$1; list=/var/lib/dpkg/info/${package}.list; inst=$(stat "$list" -c %X); cat $list | (while read file; do if [ -f "$file" ];then acc=$(stat "$file" -c %X); if [ $inst -lt $acc ]; then echo used $file; exit 0; fi; fi; done; exit 1)
2010-09-20 18:10:19
User: pipeliner
Functions: cat echo exit read stat
Tags: apt dpkg date stat
1
Up
Down
Check if the Debian package was used since its installation/upgrade.

This script compares the modification date of /var/lib/dpkg/info/${package}.list and all the files mentioned there.

It could be wrong on noatime partitions.

Here is non-oneliner:

#!/bin/sh

package=$1;

list=/var/lib/dpkg/info/${package}.list;

inst=$(stat "$list" -c %X);

cat $list |

(

while read file; do

if [ -f "$file" ]; then

acc=$(stat "$file" -c %X);

if [ $inst -lt $acc ]; then

echo used $file

exit 0

fi;

fi;

done

exit 1

)

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cat VIDEO_TS/VTS_01_[1234].VOB | nice ffmpeg -i - -s 512x384 -vcodec libtheora -acodec libvorbis ~/Videos/dvd_rip.ogg
2010-09-14 14:45:27
User: zhangweiwu
Functions: cat nice
Tags: ffmpeg dvd
5
Up
Down
DVD ripping with ffmpeg

To rip DVD movie to ogg format using ffmpeg, follow these steps.

1) find the vob files on the mounted video DVD in VIDEO_TS that stores the movie itself. There would be a few other VOB files that stores splash screen or special features, the vob files for the movie itself can be identified by its superior size. You can verify these vob files by playing them directly with a player (e.g. mplayer)

2) concatenate all such vob files, pipe to ffmpeg

3) calculate the video size and crop size. The ogg video size must be multiple of 16 on both width and height, this is inherit limitation of theora codec. In my case I took 512x384.

The -vcodec parameter is necessary because ffmpeg doesn't support theora by itself. -acodec is necessary otherwise ffmpeg uses flac by default.

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