Commands tagged perl | commandlinefu.com

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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

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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="[email protected]";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

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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="[email protected]";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

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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="[email protected]";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="[email protected]";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

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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.

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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

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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 '@f=<>; 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

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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

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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.

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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

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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... )

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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

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perl one-liner to get the current week number

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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

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Match a URL

don't have to be that complicated

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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

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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

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urldecoding

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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

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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

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List your largest installed packages (on Debian/Ubuntu)

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

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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

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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

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Transforms a file to all uppercase.

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perl -we 'my $regex = eval {qr/.*/}; die "[email protected]" if [email protected];'

2009-10-13 21:50:47

User: tlacuache

Functions: eval perl

Tags: perl regex validation

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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

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Transforms a file to all uppercase.

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

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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

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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

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Randomize lines (opposite of | sort)

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

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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

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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.

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cat ~/SortedFile.txt | perl -wnl -e '@f=<>; 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

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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

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Dump all of perl's config info

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

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find $HOME -type f -print0 | perl -0 -wn -e '@f=<>; 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

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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

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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

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