Commands using perl | commandlinefu.com

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Terminal - Commands using perl - 335 results

tail -F some.log | perl -ne 'print time(), "\n";' | uniq -c

2013-05-11 04:51:22

User: grana

Functions: perl tail uniq

Tags: tail wc

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Lines per second in a log file

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ps -e -m -o user,pid,args,%mem,rss | grep Chrome | perl -ne 'print "$1\n" if / (\d+)$/' | ( x=0;while read line; do (( x += $line )); done; echo $((x/1024)) );

2013-05-07 22:50:44

User: unixmonkey39631

Functions: echo grep perl ps read

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Chrome sucks

How much memory is chrome sucking?

pwd|grep -o '/'|perl -ne '$x.="./.";print`readlink -f $x`'|xargs -tn1 chmod 755

2013-03-14 12:03:44

User: luke_skywalker

Functions: chmod grep perl pwd xargs

Tags: perl xargs grep chmod

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Ensure path permissions from '.' prior to root

`pwd` returns the current path

`grep -o` prints each slash on new line

perl generates the paths sequence: './.', './../.', ...

`readlink` canonicalizes paths (it makes the things more transparent)

`xargs -tn1` applies chmod for each of them. Each command applied is getting printed to STDERR.

for i in `gpg --list-sigs | perl -ne 'if(/User ID not found/){s/^.+([a-fA-F0-9]{8}).*/\1/; print}' | sort | uniq`; do gpg --keyserver-options no-auto-key-retrieve --recv-keys $i; done

2013-03-10 09:15:15

User: hank

Functions: gpg perl sort

Tags: bash GPG sed fetch

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Fetch all GPG keys that are currently missing in your keyring

The original command doesn't work for me - does something weird with sed (-r) and xargs (-i) with underscores all over...

This one works in OSX Lion. I haven't tested it anywhere else, but if you have bash, gpg and perl, it should work.

curl http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html 2>/dev/null | grep '^<h3' | grep -v '^\d' | perl -pe 's/^.*(?<=(\d\d\d)) (.*)<\/h3>$/$1 : $2/' | grep -v h3

2013-03-06 01:49:08

User: klg

Functions: grep perl

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Get a list of HTTP status codes

When you need a quick ref guide while troubleshooting Apache|NGINX error|access logs.

wget -q -O - http://listen.di.fm/public2 | sed 's/},{/\n/g' | perl -n -e '/"key":"([^"]*)".*"playlist":"([^"]*)"/; print "$1\n"; system("wget -q -O - $2 | grep -E '^File' | cut -d= -f2 > di_$1.m3u")'

2013-02-20 03:37:41

User: Zort

Functions: perl sed wget

Tags: playlist mpd digitally imported

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MPD + Digitally Imported

1.- Enter into the playlist path.

2.- Run the command.

3.- Playlists created!

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FULLPATH=$(perl -e "use Cwd 'abs_path';print abs_path('$0');")

2013-02-01 20:09:34

User: follier

Functions: perl

Tags: perl cd dirname pwd variable cwd abs_path

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Get full directory path of a script regardless of where it is run from

Since none of the systems I work on have readlink, this works cross-platform (everywhere has perl, right?).

Note: This will resolve links.

perl -MModule::Name\ 9999 -e 1

2013-01-15 22:51:39

User: three18ti

Functions: perl

Tags: bash perl zsh

-1

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Find out if a module is installed in perl (and what version)

This attempts to load a Perl Module (-M flag) and use version 9999, since no module has a version this high, Perl exits either a) telling you the version of the module installed or b) tells you it can't find the module.

module_exists(){ perl -e 'use '$1 2>/dev/null; }

2013-01-11 14:47:07

User: putnamhill

Functions: perl

Tags: bash perl

-2

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Find out if a module is installed in perl

This version uses a bash function and does not print the path to the module.

perl -MFile::Find=find -MFile::Spec::Functions -Tlwe '$found=1; find { wanted => sub { if (/$ARGV[0]\.pm\z/) { print canonpath $_; $found=0; } }, no_chdir => 1 }, @INC; exit $found;' Collectd/Plugins/Graphite

2013-01-11 11:01:46

User: keymon

Functions: exit find perl

-2

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Find out if a module is installed in perl

Will check if the given module is installed in the @INC. It will print the path and return 0 if found, or 1 otherwise.

Based on script from SharpyWarpy in http://www.linuxquestions.org/questions/linux-general-1/how-to-list-all-installed-perl-modules-216603/

find . | xargs perl -p -i.bak -e 's/oldString/newString/;'

2012-11-28 17:11:18

User: RedFox

Functions: find perl xargs

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Find and replace text within all files within a directory

find . = will set up your recursive search. You can narrow your search to certain file by adding -name "*.ext" or limit buy using the same but add prune like -name "*.ext" -prune

xargs =sets it up like a command line for each file find finds and will invoke the next command which is perl.

perl = invoke perl

-p sets up a while loop

-i in place and the .bak will create a backup file like filename.ext.bak

-e execute the following....

's/ / /;' your basic substitute and replace.

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perl -E 'say $_,`tput setb $_`," "x(`tput cols`-length("$_")),`tput sgr0` for 0..(`tput colors`-1)'

2012-11-22 01:55:51

User: MarxBro

Functions: perl

Tags: perl color tput

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Show all available colors on your terminal.

Using perl and tput, show all the colors with numbers that your actual $TERM can handle.

If want to remove the numbers at beginning of new line, it should be something like this:

perl -E 'say `tput setb $_`," "x `tput cols`, `tput sgr0` for 0 .. (`tput colors` - 1)'

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perl -E 'say$_%15?$_%3?$_%5?$_:Buzz:Fizz:Fizzbuzz for 1..100'

2012-11-18 05:47:29

User: MarxBro

Functions: perl

Tags: perl fizzbuzz

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FizzBuzz in Perl

Just another FizzBuzz in Perl.

perl -e 'print "$_=$ENV{$_}\n" for keys %ENV'

2012-11-12 13:14:28

User: sgikas

Functions: perl

Tags: perl environment

-1

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Print environment information.

p=1 ; lynx -source http://www.lipsum.com/feed/xml?amount=${p} | grep '<lipsum>' -A$(((p-1))) | perl -p -i -e 's/\n/\n\n/g' | sed -n '/<lipsum>/,/<\/lipsum>/p' | sed -e 's/<[^>]*>//g'

2012-10-24 14:11:52

User: nublaii

Functions: grep perl sed

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Get Lorum Ipsum random text from lorumipsum.com

This fixes the extra lines you get when you request only 1 paragraph using a little bit of grep. Just set p to the number of paragraphs you want.

history | perl -pe "~s/ *[0-9]+ *//"

2012-10-23 22:14:00

User: tomrag

Functions: perl

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display bash history without line numbers

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perl -pi -e 's/:([\w\d_]+)(\s*)=>/\1:/g' **/*.rb

2012-10-16 16:54:40

User: asux

Functions: perl

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Convert Ruby 1.8 to 1.9 hash syntax

Stolen from http://robots.thoughtbot.com/post/17450269990/convert-ruby-1-8-to-1-9-hash-syntax

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# strace ... | perl -lne '@F=split(/\\/, $_);for(@F){push @ddd, sprintf("%x", oct("0" . $_))}END{shift @ddd; print pack("H*", join("", @ddd));}'

2012-10-16 14:24:13

User: zwxajh

Functions: perl strace

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change binary string readable

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perl -e 'print map { $_ .= "$ENV{$_}\n" } (keys %ENV)'

2012-10-13 23:38:28

User: MarxBro

Functions: perl

Tags: perl environment

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Print environment information.

Print environment (system) information using Perl.

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perl -MHTML::Entities -ne 'print encode_entities($_)' /tmp/subor.txt

2012-10-11 08:31:14

User: brx75x

Functions: perl

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encode HTML entities

Encode HTML entities supporting UTF-8 input and output

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perl -e '$|++; while (1) { print " " x (rand(35) + 1), int(rand(2)) }'

2012-09-27 22:46:39

User: MarxBro

Functions: perl

Tags: random Matrix

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Binary digits Matrix effect

Silly Perl variant.

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cat log | perl -ne 'use POSIX; s/([\d.]+)/strftime "%y-%m-%d %H:%M:%S", localtime $1/e,print if /./'

2012-09-19 06:38:31

User: bs

Functions: cat perl

Tags: time unixtime human-readable timet

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convert unixtime to human-readable

works where perl works, because the awk version is gnu awk only.

perl -e '$s="$s\xFF" while length($s)<512; print $s while 1' | dd of=/dev/sdX

2012-08-20 05:33:28

User: stonefoz

Functions: dd perl

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Fill a hard drive with ones - like zero-fill, but the opposite :)

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ping g.co|perl -ne'$|=/e=(\S+)/||next;(push@_,$1)>30&&shift@_;print"\r",(map{"\xe2\x96".chr(128+7*$_/(sort{$b<=>$a}@_)[0])." "}@_),"$1ms"'

2012-07-06 22:42:06

User: bartgrantham

Functions: perl ping

Tags: perl ping graph sparkline

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Text graphing ping output filter

Nasty perl one-liner that provides a sparkline of ping times. If you want a different history than the last 30, just put that value in. It (ab)uses unicode to draw the bars, inspired by https://github.com/joemiller/spark-ping . It's not the most bug-free piece of code, but what it lacks in robustness it makes up for in capability. :)

If anyone has any ideas on how to make it more compact or better, I'd love to hear them.

I included a ping to google in the command just as an example (and burned up 10 chars doing it!). You should use it with: $ ping example.com | $SPARKLINE_PING_COMMAND

perl -e 'printf "00:16:3E:%02X:%02X:%02X\n", rand 0xFF, rand 0xFF, rand 0xFF'

2012-07-02 09:59:43

User: Gular

Functions: perl

Tags: perl oneliner random generate mac address

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Perl One Liner to Generate a Random IP Address

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