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Commands tagged perl from sorted by
Terminal - Commands tagged perl - 167 results
perl -e 'chomp($k=`uname -r`); for (</boot/vm*>) {s/^.*vmlinuz-($k)?//; $l.="linux-image-$_ ";} system "aptitude remove $l";'
2010-06-10 22:16:47
User: dbbolton
Functions: perl
Tags: Debian Linux perl kernel aptitude
1
Up
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Remove all unused kernels with apt-get

TIMTOWTDI

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for code in $(find . -type f -name '*.p[ml]'); do perl -c "$code"; done
2010-05-29 23:26:40
User: udog
Functions: find perl
Tags: perl directory syntax
0
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Check syntax of all Perl modules or scripts underneath the current directory

Finds all *.p[ml]-files and runs a perl -c on them, checking whether Perl thinks they are syntactically correct

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perl -e 'foreach (@ARGV) {@T=stat($_); print localtime($T[8])." - ".$_."\n"}'
2010-05-20 16:19:17
User: putnamhill
Functions: perl
Tags: perl solaris ls file time
0
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Print time and year of file in Solaris (or other Unix ls command that does not have a simple
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perl -e '@F = `ls -1`;while (<@F>){@T = stat($_);print "$_ = " . localtime($T[8]) . "\n";}'
2010-05-20 15:02:51
User: hckhckhck
Functions: perl
Tags: perl solaris ls file time
0
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Print time and year of file in Solaris (or other Unix ls command that does not have a simple "--full-list")

Solaris 'ls' command does not have a nice '--full-time' arg to make the time show after a year has passed. So I spit this out quick. It hates spaces in file names.

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perl -MDigest::SHA -e 'print substr( Digest::SHA::sha256_base64( time() ), 0, $ARGV[0] ) . "\n"' <length>
2010-04-30 21:45:46
User: udog
Functions: perl
Tags: perl password random base64 sha256
1
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Produce a pseudo random password with given length in base 64

Of course you will have to install Digest::SHA and perl before this will work :)

Maximum length is 43 for SHA256. If you need more, use SHA512 or the hexadecimal form: sha256_hex()

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echo $hex | perl -pe 's/(..)/chr(hex($1))/ge'
2010-04-17 16:24:48
User: dfaulkner
Functions: echo perl
Tags: perl strings hex ascii convert
0
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convert a string of hex characters into ascii chars
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perl -i -pe 's/\r/\n/g' file
2010-04-16 13:25:09
User: octopus
Functions: perl
Tags: Linux perl unix
0
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Legacy MacOS to Unix text convert using perl
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perldoc perllocal
2010-04-14 10:57:56
User: octopus
Tags: version perl
3
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List all installed PERL modules by CPAN

This command will give you the detailed information about the installed perl modules i.e. installed path, Link type, version, files etc.

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curl -s http://api.wunderground.com/auto/wui/geo/ForecastXML/index.xml?query=${@:-<YOURZIPORLOCATION>}|xmlstarlet sel -E utf-8 -t -m //forecast/txt_forecast/forecastday -v fcttext -n
2010-04-13 22:14:48
User: fanfani
Tags: perl curl function weather
-2
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Get the weather forecast for the next 24 to 48 for your location.

you can use xmlstarlet to parse output instead of perl

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perl -MStatistics::Descriptive -alne 'my $stat = Statistics::Descriptive::Full->new; $stat->add_data(@F[1..4]); print $stat->variance' filename
2010-04-02 21:16:12
User: alperyilmaz
Functions: perl
Tags: statistics perl math
1
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statistics in one line

In this example, file contains five columns where first column is text. Variance is calculated for columns 2 - 5 by using perl module Statistics::Descriptive. There are many more statistical functions available in the module.

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perl -pi -e 's/\r\n?/\n/g'
2010-03-18 17:48:16
User: putnamhill
Functions: perl
Tags: perl
3
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Convert files from DOS line endings to UNIX line endings

This method will also convert mac line endings.

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perl -ne 'BEGIN{undef $/}; print "$ARGV\t$.\t$1\n" if m/(first line.*\n.*second line)/mg'
2010-03-18 15:46:10
User: hfs
Functions: perl
Tags: perl grep
7
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Multi-line grep

Using perl you can search for patterns spanning several lines, a thing that grep can't do. Append the list of files to above command or pipe a file through it, just as with regular grep. If you add the 's' modifier to the regex, the dot '.' also matches line endings, useful if you don't known how many lines you need are between parts of your pattern. Change '*' to '*?' to make it greedy, that is match only as few characters as possible.

See also http://www.commandlinefu.com/commands/view/1764/display-a-block-of-text-with-awk to do a similar thing with awk.

Edit: The undef has to be put in a begin-block, or a match in the first line would not be found.

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echo "$url" | perl -MURI::Escape -ne 'chomp;print uri_escape($_),"\n"'
2010-02-13 00:44:48
User: eightmillion
Functions: echo perl
Tags: perl
5
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Url Encode

Converts reserved characters in a URI to their percent encoded counterparts.

Alternate python version:

echo "$url" | python -c 'import sys,urllib;print urllib.quote(sys.stdin.read().strip())'
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weather(){ curl -s "http://api.wunderground.com/auto/wui/geo/ForecastXML/index.xml?query=${@:-<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
7
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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

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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
7
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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

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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
18
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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="$@";curl -sA"Opera" "http://www.google.com/search?q=define:${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;}
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podwebserver& sleep 2; elinks 'http://127.0.0.1:8020'
2010-01-27 10:57:34
User: vlan7
Functions: sleep
Tags: perl firefox server
5
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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
13
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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>

or

<SOMECOMMAND> | grepp <PATTERN>
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perl -wl -e '@f=<>; for $i (0 .. $#f) { $r=int rand ($i+1); @f[$i, $r]=@f[$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
0
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Randomize lines (opposite of | sort)

print the lines of a file in randomized order

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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
0
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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
1
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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
Up
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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
Up
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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
0
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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.

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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
4
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urldecoding
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