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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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Commands using perl from sorted by
Terminal - Commands using perl - 346 results
perl -e 'for (<*.mp3>) { $old = $_; s/ /-/g; rename $old, $_ }'
#(see sample) $ cat x | perl -pe 'BEGIN{ print "TIME;...\n"; } s!(\S+) - (\S+) - \[(\d\d)/(\S\S\S)/(\S+):(\d\d):(\d\d:\d\d) \S+\] "(\S+) (.*/)(\S+)(?:\.([^?]*)(\?\S*)?) HTTP/\S+" (\d+) (\S+)!$3-$4-$5 $6:$7;$6;$2;$1;$8;$13;1;$14;$11;$10;$9;$12;!' > x.csv
2012-02-10 16:58:50
User: hute37
Functions: cat perl

- excel date compatible with a separate hour field

- added a fixed 1 for easier request counter aggregation

- split URL in directory, filename, fileext, query

- used with tomcat valve with response bytes replaced by elapsed time

du -k | sort -n | perl -ne 'if ( /^(\d+)\s+(.*$)/){$l=log($1+.1);$m=int($l/log(1024)); printf ("%6.1f\t%s\t%25s %s\n",($1/(2**(10*$m))),(("K","M","G","T","P")[$m]),"*"x (1.5*$l),$2);}' | more
2012-02-07 15:49:19
User: Q_Element
Functions: du perl printf sort

This one line Perl script will display the smallest to the largest files sizes in all directories on a server.

useradd -m -p $(perl -e'print crypt("passwordscelta", "stigghiola")') user
2012-02-06 19:53:01
User: 0disse0
Functions: perl useradd

The crypt function takes a password, key, as a string, and a salt character array which is described below, and returns a printable ASCII string which starts with another salt. It is believed that, given the output of the function, the best way to find a key that will produce that output is to guess values of key until the original value of key is found.

from http://en.wikipedia.org/wiki/Crypt_(Unix)

perl -i -ne 'print if $. == 3..5' <filename>
genRandomText() { perl -e '$n=shift; print chr(int(rand(26)) + 97) for 1..$n; print "\n"' $1;}
2012-01-21 00:21:20
User: putnamhill
Functions: perl

If you don't have seq, you can use perl.

perl -p -i -e 's/.*\n//g if $.==2' ~/.ssh/known_hosts
perl -le 'print$_%3?$_%5?$_:"Buzz":$_%5?"Fizz":"FizzBuzz"for 1..100'
comm -13 <(od -vw1 -tu1 dummy.txt|cut -c9-|sort -u) <(seq 0 127|sort)|perl -pe '$_=chr($_)'|od -c
2012-01-09 01:32:20
User: bazzargh
Functions: comm cut od perl seq sort
Tags: bash

Search in decimal rather than hex. od dumps the character list, cut to remove offsets, sort -u gives the used characters. seq gives the comparison list, but we need this sorted alphabetically for comm, which does the filtering. I drop to perl to convert back to characters (is there a better way?) and then use od to dump them in a print-safe format.

find . -type f|perl -lne '@x=sort {$b->[0]<=>$a->[0]}[(stat($_))[7],$_],@x;splice(@x,11);print "@{$x[0]}";END{for(@x){print "@$_"}'
2012-01-08 14:43:43
User: bazzargh
Functions: find perl
Tags: sort perl find

A different approach to the problem - maintain a small sorted list, print the largest as we go, then the top 10 at the end. I often find that the find and sort take a long time, and the large file might appear near the start of the find. By printing as we go, I get better feedback. The sort used in this will be much slower on perls older than 5.8.

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 \"[email protected]\""; 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]).

cvs -Q status | perl -ne 'print if m/^File.+Status: (?!Up-to-date)/ .. m/^=/;'
2011-12-07 00:33:49
User: dexterp
Functions: cvs perl

This will also print the path to file which is not included in the other examples.

find . -iregex ".+\.\(c\|cpp\|h\)" | xargs -I{} perl -e "system(\"iconv -f SHIFT_JIS -t UTF-8 {} > temp; mv temp {} \");" ;
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

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 f in $(ls -A ./dir); do echo -n $f && diff original.txt ./dir/$f | wc -l ; done | perl -ne 'my $h={}; while (<>) { chomp; if (/^(\S+?)\s*(\d+?)$/){$h->{$1}=$2;} }; for my $k (sort { $h->{$a} $h->{$b} } keys %$h ){ print "$k\t$h->{$k}\n"}'
perl -ane 'END{printf(" %d %d %d\n", $x, $y, $z)} $x+=1; [email protected]; $z+=length' file.txt
perl -C -e 'print for sort { length $a <=> length $b or $a cmp $b } <>' < /usr/share/dict/words | tail
2011-10-20 01:43:25
User: dbr
Functions: cmp perl sort

making it "sound" more "natural" language like -- additionally sorting the longest words alphabetically:

this approach is using:

* to get at all lines of input

* post-"for" structure

* short-circuit-or in sort: if the lengths are the same, then sort alphabetically otherwise don't even evaluate the right hand side of the or

* -C sets all input and ouput channels to utf8

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 -MAcme::POE::Tree -e 'Acme::POE::Tree->new()->run()'