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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!

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Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Commands tagged perl from sorted by
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

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

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

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

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 ''
2010-01-27 10:57:34
User: vlan7
Functions: sleep

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(, new-tab )'

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

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

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>


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
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

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.

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

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... )

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

don't have to be that complicated

echo "(Something like http://foo.com/blah_blah)" | grep -oP "\b(([\w-]+://?|www[.])[^\s()<>]+(?:\([\w\d]+\)|([^[:punct:]\s]|/)))"
perl -pe 's/%([0-9a-f]{2})/sprintf("%s", pack("H2",$1))/eig'
utime(){ perl -e "print localtime($1).\"\n\"";}
2009-11-06 12:58:10
User: MoHaG
Functions: perl

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)

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

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
perl -we 'my $regex = eval {qr/.*/}; die "$@" if $@;'
2009-10-13 21:50:47
User: tlacuache
Functions: eval perl

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
Functions: perl
Tags: perl

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

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

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>
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

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

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

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

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

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

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

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"

it will only print the "" portion