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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:

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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
perl -e '$f = join("", <>); for (0..127) {$_ = chr($_); if (/[[:print:]]/) {print if index($f, $_) < 0}} print "\n"'
2012-01-05 23:38:06
User: putnamhill
Functions: perl
Tags: perl slurp

Here's a perl version that only considers printable characters. Change the regex /[[:print:]]/ to look for different sets of delimiter characters.

perl -e "binmode(STDOUT, ':utf8'); print \"$@\""; echo # newline
2012-01-02 10:34:51
User: mathias
Functions: echo perl

This is especially useful to get crazy stuff like space characters copied to your pasteboard correctly.

Source: https://github.com/mathiasbynens/dotfiles/blob/master/.functions

perl -ne 's/\^.{1,7}?m//g;print'
2012-01-02 01:32:33
User: Tracerneo
Functions: perl
Tags: perl regex colors

Removes special characters (colors) in '^]]Xm' and '^]]X;Ym' format from file.

Use pipe ('input | perl [...]') or stream ('perl [...]

You can use 'cat -v infile' as 'input' to show special characters instead of interpreting (there is problem with non-ASCII chars, they are replaced by M-[char]).

mplayer -endpos 0.1 -vo null -ao null -identify *.avi 2>&1 |grep ID_LENGTH |cut -d = -f 2|awk '{SUM += $1} END { printf "%d:%d:%d\n",SUM/3600,SUM%3600/60,SUM%60}'
lsmod | perl -e 'print "digraph \"lsmod\" {";<>;while(<>){@_=split/\s+/; print "\"$_[0]\" -> \"$_\"\n" for split/,/,$_[3]}print "}"' | dot -Tpng | display -
2011-11-27 14:02:35
User: bandie91
Functions: dot lsmod perl

parse `lsmod' output and pass to `dot' drawing utility then finally pass it to an image viewer

mech-dump --links --absolute http://www.commandlinefu.com
2011-11-19 03:40:52
User: sputnick
Tags: perl html parsing

You need to install WWW::Mechanize Perl module with

# cpan -i WWW::Mezchanize

or by searching mechanize | grep perl in your package manager

With this command, you can get forms, images, headers too

perl -MO=Deparse filename.pl | perltidy > new.pl
2011-11-16 18:54:30
User: kimmel
Functions: perl

This will create a new file with proper code formatting and all comments removed.

perl -le 'print scalar gmtime shift' 1234567890
perl -MExtUtils::Installed -E 'say for ExtUtils::Installed->new()->modules()'
2011-11-16 17:26:47
User: kimmel
Functions: perl
Tags: perl oneliner

Lists all the modules that were installed the "proper way". It also uses Perl 5.10(or higher)'s say command for less typing.

for k in `git branch|sed s/^..//`;do echo -e `git log -1 --pretty=format:"%Cgreen%ci %Cblue%cr%Creset" "$k" --`\\t"$k";done|sort
2011-11-02 06:16:22
User: ryan
Functions: echo sed

This fixes a bug found in the other scripts which fail when a branch has the same name as a file or directory in the current directory.

perl -ane 'END{printf(" %d %d %d\n", $x, $y, $z)} $x+=1; [email protected]; $z+=length' file.txt
svn log | perl -pe 's/\n//g => s/^-.*/\n/g'
2011-10-20 01:20:52
User: dbr
Functions: perl
Tags: svn perl svn log

dirrrty: use -p to chomp automatically, substitute all newlines away and then replace the "---" by a newline ? bingo!

s/// => s/// is just a cooler way to write s///, s/// which is just the small brother of s///; s/// (comma is an operator!)

have fun!

svn log | perl -l40pe 's/^-+/\n/'
2011-10-14 16:02:22
User: bazzargh
Functions: perl
Tags: svn perl svn log

the output of svn log is annoying to grep, since it spreads the useful info over multiple lines. This compacts the output down to one line so eg you can grep for a comment and see the rev, date & committer straight away.

Updated: MUCH shorter, easier to remember. Now it just replaces newlines with spaces, except on '---' lines.

perl -i -pe 'BEGIN{undef $/;} s/START.*?STOP/replace_string/smg' file_to_change
tail -f LOGFILE | perl -ne '`say "$_"`;'
2011-09-16 05:33:22
User: tamouse
Functions: perl tail
Tags: perl tail say

say only processes a complete file, at eof, so following a file isn't possible. Quick and dirty perl oneliner to feed each line from the tail -f to say. Yes, expensive to lauch a new process each line.

This little ditty was prompted by a discussion on how horrible it is to use VoiceOver on ncurses programs such as irssi.

sudo find / -type f | perl -MFile::Basename -ne '$counts{dirname($_)}++; END { foreach $d (sort keys %counts) {printf("%d\t%s\n",$counts{$d},$d);} }'|sort -rn | tee /tmp/sortedfilecount.out | head
2011-09-14 19:41:19
User: tamouse
Functions: find perl sort sudo tee

Find which directories on your system contain a lot of files.

Edit: much shorter and betterer with -n switch.

cd /path/to/pmwiki/wiki.d;/bin/ls -1 | perl -ne 'my ($group,$name)=split(/\./);$counts{$group}++;' -e 'END { foreach $group (sort keys %counts) {printf("%d\t%s\n",$counts{$group},$group);} }'|sort -rn
2011-09-14 19:33:39
User: tamouse
Functions: cd perl sort
Tags: sort perl pmwiki

PmWiki stores wiki pages as Group.Name. Simply split the directory listing and count frequency of group occurances.

route -n | perl -ne '$ANY=""; /^$ANY/ and split /\s+/ and print "Gateway to the World: ",($_[1]!=$ANY)?$_[1]:(`ip address show $_[$#_]`=~/peer ([0-9\.]+)/ and $1),", via $_[$#_].\n"'
wget -q -O - http://www.perl.org/get.html | grep -m1 '\.tar\.gz' | sed 's/.*perl-//; s/\.tar\.gz.*//'
curl -s http://www.perl.org/get.html | grep -m1 '\.tar\.gz' | sed 's/.*perl-//; s/\.tar\.gz.*//'
find /var/spool/mqueue -type f -mtime +7 | perl -lne unlink
2011-08-19 15:22:02
User: mengesb
Functions: find perl

Find all files in /var/spool/mqueue older than 7 days, pass to perl to efficiently delete them (faster than xargs or -exec when you've got millions or hundreds of thousands to delete). Naturally the type, directory, and file age vars can be adjusted to meet your specific needs.

ack; pcregrep
2011-08-14 18:01:36
User: depesz
Tags: perl grep regex

Much better alternatives - grep-alikes using perl regexps. With more options, and nicer outputs.

prep () { perl -nle 'print if '"$1"';' $2 }
2011-08-13 14:29:26
User: dbbolton
Functions: perl
Tags: perl grep regex

If you've ever tried "grep -P" you know how terrible it is. Even the man page describes it as "highly experimental". This function will let you 'grep' pipes and files using Perl syntax for regular expressions.

The first argument is the pattern, e.g. '/foo/'. The second argument is a filename (optional).

cat subtitles.txt | perl -pe 's/} /}/g; s/{(\d+)}/=1=/; $f1=(24/25*$1); s/{(\d+)}/=2=/; $f2=(24/25*$1); $f1=~s/\..*//; $f2=~s/\..*//; s/=1=/{$f1}/; s/=2=/{$f2}/; ' > subtitles_newfps.txt
2011-07-30 15:34:43
User: ciekawy
Functions: cat perl

this command example converts to 25 fps subtitles that were originally created for 24 fps movie

lsof -nPi | txt2html > ~/lsof.html
2011-07-28 14:01:21
User: zlemini
Tags: perl cpan lsof

The output of lsof is piped to txt2html which converts it to html.

# Perl module HTML::TextToHTML needed