Commands tagged perl | commandlinefu.com

Hide

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again.

Delete that bloated snippets file you've been using and share your personal repository with the world. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Get involved!

You can sign-in using OpenID credentials, or register a traditional username and password.

OpenID

First-time OpenID users will be automatically assigned a username which can be changed after signing in.

UpGuard checks and validates configurations for every major OS, network device, and cloud provider.

Hide

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for:

» all commands
» commands with 3 up-votes (commandlinefu3)
» commands with 10 up-votes (commandlinefu10)
» commands tagged perl

Hide

News

May 19, 2015 - A Look At The New Commandlinefu: I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management: I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

Hide

Top Tags

awk, bash, curl, find, grep, Linux, sed

Hide

Functions

Terminal - Commands tagged perl - 178 results

weather(){ curl -s "http://api.wunderground.com/auto/wui/geo/ForecastXML/index.xml?query=${@:-<YOURZIPORLOCATION>}"|perl -ne '/<title>([^<]+)/&&printf "%s: ",$1;/<fcttext>([^<]+)/&&print $1,"\n"';}

2010-02-10 01:23:39

User: eightmillion

Functions: perl

Tags: perl curl function weather

Up
Down

Get the weather forecast for the next 24 to 48 for your location.

This shell function grabs the weather forecast for the next 24 to 48 hours from weatherunderground.com. Replace <YOURZIPORLOCATION> with your zip code or your "city, state" or "city, country", then calling the function without any arguments returns the weather for that location. Calling the function with a zip code or place name as an argument returns the weather for that location instead of your default.

To add a bit of color formatting to the output, use the following instead:

weather(){ curl -s "http://api.wunderground.com/auto/wui/geo/ForecastXML/index.xml?query=${@:-<YOURZIPORLOCATION>}"|perl -ne '/<title>([^<]+)/&&printf "\x1B[0;34m%s\x1B[0m: ",$1;/<fcttext>([^<]+)/&&print $1,"\n"';}

Requires: perl, curl

define(){ local y="$@";curl -sA"Opera" "http://www.google.com/search?q=define:${y// /+}"|grep -Eo '<li>[^<]+'|sed 's/^<li>//g'|nl|/usr/bin/perl -MHTML::Entities -pe 'decode_entities($_)';}

2010-01-30 13:08:03

User: gthb

Functions: grep sed

Tags: bash perl macosx curl function google nl

Up
Down

Define words and phrases with google.

This version works on Mac (avoids grep -P, adding a sed step instead, and invokes /usr/bin/perl with full path in case you have another one installed).

Still requires that you install perl module HTML::Entities ? here's how: http://www.perlmonks.org/?node_id=640489

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

define(){ local y="$@";curl -sA"Opera" "http://www.google.com/search?q=define:${y// /+}"|grep -Po '(?<=<li>)[^<]+'|nl|perl -MHTML::Entities -pe 'decode_entities($_)' 2>/dev/null;}

2010-01-29 05:01:11

User: eightmillion

Functions: grep perl

Tags: bash perl curl function google nl

Up
Down

Define words and phrases with google.

This function takes a word or a phrase as arguments and then fetches definitions using Google's "define" syntax. The "nl" and perl portion isn't strictly necessary. It just makes the output a bit more readable, but this also works:

define(){ local y="$@";curl -sA"Opera" "http://www.google.com/search?q=define:${y// /+}"|grep -Po '(?<=<li>)[^<]+';}

If your version of grep doesn't have perl compatible regex support, then you can use this version:

define(){ local y="$@";curl -sA"Opera" "http://www.google.com/search?q=define:${y// /+}"|grep -Eo '<li>[^<]+'|sed 's/<li>//g'|nl|perl -MHTML::Entities -pe 'decode_entities($_)' 2>/dev/null;}

podwebserver& sleep 2; elinks 'http://127.0.0.1:8020'

2010-01-27 10:57:34

User: vlan7

Functions: sleep

Tags: perl firefox server

Up
Down

Do some Perl learning...

Prerequisites: module Pod::Webserver installed. You can install it typing:

sudo perl -MCPAN -e 'install Pod::Webserver'

You can replace elinks with your fav browser. For FF:

podwebserver& sleep 2; firefox -remote 'openurl( http://127.0.0.1:8020/, new-tab )'

If you have Firefox open, this will pop-up the index web in a new tab.

Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

grepp() { [ $# -eq 1 ] && perl -00ne "print if /$1/i" || perl -00ne "print if /$1/i" < "$2";}

2010-01-12 04:30:15

User: eightmillion

Functions: perl

Tags: perl grep function

Up
Down

Grep by paragraph instead of by line.

This is a command that I find myself using all the time. It works like regular grep, but returns the paragraph containing the search pattern instead of just the line. It operates on files or standard input.

grepp <PATTERN> <FILE>

<SOMECOMMAND> | grepp <PATTERN>

perl -wl -e [email protected]=<>; for $i (0 .. $#f) { $r=int rand ($i+1); @f[$i, $r][email protected][$r,$i] if ($i!=$r); } chomp @f; print join $/, @f;' try.txt

2009-12-21 21:15:55

User: JohnGH

Functions: join perl

Tags: Text Processing Os X cat sort perl sorting text

Up
Down

Randomize lines (opposite of | sort)

print the lines of a file in randomized order

perl -lne 'print for /url":"\K[^"]+/g' $(ls -t ~/.mozilla/firefox/*/sessionstore.js | sed q)

2009-12-14 00:51:54

User: sputnick

Functions: ls perl sed

Tags: perl firefox regex json substitution

Up
Down

Extract all urls from last firefox sessionstore used in a portable way.

If you want all the URLs from all the sessions, you can use :

perl -lne 'print for /url":"\K[^"]+/g' ~/.mozilla/firefox/*/sessionstore.js

Thanks to tybalt89 ( idea of the "for" statement ).

For perl purists, there's JSON and File::Slurp modules, buts that's not installed by default.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

x=IO::Interface::Simple; perl -e 'use '$x';' &>/dev/null || cpan -i "$x"; perl -e 'use '$x'; my $ip='$x'->new($ARGV[0]); print $ip->address,$/;' <INTERFACE>

2009-12-13 02:23:40

User: sputnick

Functions: perl

Tags: perl cpan shell ip address

Up
Down

Display IP adress of the given interface in a most portable and reliable way. That should works on many platforms.

Thanks to comment if that works or not...

If you have already typed that snippet or you know you already have IO::Interface::Simple perl module, you can type only the last command :

perl -e 'use IO::Interface::Simple; my $ip=IO::Interface::Simple->new($ARGV[0]); print $ip->address,$/;' <INTERFACE>

( The first perl command will install the module if it's not there already... )

Comments (7) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

perl -e 'use Date::Calc qw(Today Week_Number); $weekn = Week_Number(Today); print "$weekn\n"'

2009-12-01 20:56:13

User: imsaar

Functions: perl

Tags: perl date week

-3

Up
Down

perl one-liner to get the current week number

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cho "(Something like http://foo.com/blah_blah)" | awk '{for(i=1;i<=NF;i++){if($i~/^(http|ftp):\/\//)print $i}}'

2009-11-28 03:31:41

User: unixmonkey7109

Functions: awk

Tags: perl regex url match url matching

-1

Up
Down

Match a URL

don't have to be that complicated

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

echo "(Something like http://foo.com/blah_blah)" | grep -oP "\b(([\w-]+://?|www[.])[^\s()<>]+(?:$[\w\d]+$|([^[:punct:]\s]|/)))"

2009-11-28 00:41:57

User: matthewbauer

Functions: echo grep

Tags: perl regex url match url matching

Up
Down

Match a URL

From http://daringfireball.net/2009/11/liberal_regex_for_matching_urls

Thought it would be useful to commandlinefuers.

perl -pe 's/%([0-9a-f]{2})/sprintf("%s", pack("H2",$1))/eig'

2009-11-25 14:32:50

User: putnamhill

Functions: perl

Tags: perl urldecode

Up
Down

urldecoding

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

utime(){ perl -e "print localtime($1).\"\n\"";}

2009-11-06 12:58:10

User: MoHaG

Functions: perl

Tags: Date manipulation Linux perl solaris unix date function time zsh convert

Up
Down

Easily decode unix-time (funtion)

A shell function using perl to easily convert Unix-time to text.

Put in in your ~/.bashrc or equivalent.

Tested on Linux / Solaris Bourne, bash and zsh. using perl 5.6 and higher.

(Does not require GNU date like some other commands)

dpigs

2009-10-26 20:38:17

User: xrm0

Tags: Debian sort perl dpkg

Up
Down

List your largest installed packages (on Debian/Ubuntu)

dpigs is in the package debian-goodies (debian/ubuntu)

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

perl -ne '$pkg=$1 if m/^Package: (.*)/; print "$1\t$pkg\n" if m/^Installed-Size: (.*)/;' < /var/lib/dpkg/status | sort -rn | less

2009-10-19 12:55:59

User: hfs

Functions: perl sort

Tags: Debian sort perl dpkg

Up
Down

List your largest installed packages (on Debian/Ubuntu)

List packages and their disk usage in decreasing order. This uses the "Installed-Size" from the package metadata. It may differ from the actual used space, because e.g. data files (think of databases) or log files may take additional space.

perl -i -ne 'print uc $_' $1

2009-10-15 16:59:38

User: rbs

Functions: perl

Tags: perl

-1

Up
Down

Transforms a file to all uppercase.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

perl -we 'my $regex = eval {qr/.*/}; die "$@" if $@;'

2009-10-13 21:50:47

User: tlacuache

Functions: eval perl

Tags: perl regex validation

Up
Down

validate the syntax of a perl-compatible regular expression

Place the regular expression you want to validate between the forward slashes in the eval block.

perl -pi -e 's/([[:lower:]]+)/uc $1/gsex' file

2009-10-08 14:18:50

User: linuxrawkstar

Functions: perl

Tags: perl

-2

Up
Down

Transforms a file to all uppercase.

same, except it works on any OS with Perl installed. DOS, Windose, whatever

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

curl "http://www.house.gov/house/MemberWWW.shtml" 2>/dev/null | sed -e :a -e 's/<[^>]*>//g;/</N;//ba' | perl -nle 's/^\t\t(.*$)/ $1/ and print;'

2009-09-24 23:37:36

User: drewk

Functions: perl sed

Tags: perl sed curl

-1

Up
Down

Print all members of US House of Representatives

Uses curl to download page of membership of US Congress. Use sed to strip HTML then perl to print a line starting with two tabs (a line with a representative)

random -f <file>

2009-09-24 19:15:58

User: haplo

Tags: Text Processing Os X cat sort perl sorting text

Up
Down

Randomize lines (opposite of | sort)

random(6) - random lines from a file or random numbers

Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

find -type f -name "*.avi" -print0 | xargs -0 mplayer -vo dummy -ao dummy -identify 2>/dev/null | perl -nle '/ID_LENGTH=([0-9\.]+)/ && ($t +=$1) && printf "%02d:%02d:%02d\n",$t/3600,$t/60%60,$t%60' | tail -n 1

2009-09-24 15:50:39

User: syssyphus

Functions: find perl printf tail xargs

Tags: video audio mplayer perl find

Up
Down

Get the total length of all video / audio in the current dir (and below) in H:m:s

change the *.avi to whatever you want to match, you can remove it altogether if you want to check all files.

Comments (77) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

cat ~/SortedFile.txt | perl -wnl -e [email protected]=<>; END{ foreach $i (reverse 0 .. $#f) { $r=int rand ($i+1); @f[$i, $r][email protected][$r,$i] unless ($i==$r); } chomp @f; foreach $line (@f){ print $line; }}'

2009-09-24 15:42:43

User: drewk

Functions: cat perl

Tags: Text Processing Os X cat sort perl sorting text

Up
Down

Randomize lines (opposite of | sort)

The sort utility is well used, but sometimes you want a little chaos. This will randomize the lines of a text file.

BTW, on OS X there is no

| sort -R

option! There is also no

| shuf

These are only in the newer GNU core...

This is also faster than the alternate of:

| awk 'BEGIN { srand() } { print rand() "\t" $0 }' | sort -n | cut -f2-

perl -le 'use Config; foreach $i (keys %Config) {print "$i : @Config{$i}"}'

2009-09-22 22:14:21

User: chuckr

Functions: perl

Tags: perl

Up
Down

Dump all of perl's config info

This dumps all of your installed perl's config information.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

find $HOME -type f -print0 | perl -0 -wn -e [email protected]=<>; foreach $file (@f){ (@el)=(stat($file)); push @el, $file; push @files,[ @el ];} @o=sort{$a->[9]<=>$b->[9]} @files; for $i (0..$#o){print scalar localtime($o[$i][9]), "\t$o[$i][-1]\n";}'|tail

2009-09-21 22:11:16

User: drewk

Functions: find perl

Tags: bash perl awk tail find xargs HEAD stat

Up
Down

Find and display most recent files using find and perl

This pipeline will find, sort and display all files based on mtime. This could be done with find | xargs, but the find | xargs pipeline will not produce correct results if the results of find are greater than xargs command line buffer. If the xargs buffer fills, xargs processes the find results in more than one batch which is not compatible with sorting.

Note the "-print0" on find and "-0" switch for perl. This is the equivalent of using xargs. Don't you love perl?

Note that this pipeline can be easily modified to any data produced by perl's stat operator. eg, you could sort on size, hard links, creation time, etc. Look at stat and just change the '9' to what you want. Changing the '9' to a '7' for example will sort by file size. A '3' sorts by number of links....

Use head and tail at the end of the pipeline to get oldest files or most recent. Use awk or perl -wnla for further processing. Since there is a tab between the two fields, it is very easy to process.

perl -wlne 'print $1 if /(([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5]))/' iplist

2009-09-17 16:14:52

User: salparadise

Functions: perl

Tags: perl IP regex ip address

-1

Up
Down

regex to match an ip

if you want to only print the IP address from a file.

In this case the file will be called "iplist" with a line like "ip address 1.1.1.1"

it will only print the "1.1.1.1" portion

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

‹ First < 4 5 6 7 8 >