Commands using perl sorted by votes

Commands using perl (369)

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let the cow suggest some commit messages for you

I used curl instead of lynx. Show Sample Output
This is sample output - yours may be different.
```
 _______________________
< omg what have I done? >
 -----------------------
        \   ^__^
         \  (oo)\_______
            (__)\       )\/\
                ||----w |
                ||     ||
```
0

while true; do curl -s http://whatthecommit.com | perl -p0e '($_)=m{<p>(.+?)</p>}s' | cowsay; sleep 2; done

seungwon · 2011-01-30 02:17:41 3
Convert Unix newlines to DOS newlines

Let -p do it's voodoo and do absolutely nothing but set the output record separator :-)
This is sample output - yours may be different.
0

perl -ple 'BEGIN { $\ = "\r\n" }'

coffeeaddict_nl · 2011-03-01 09:45:37 3
Change your exported xml love list from last.fm, into Song: songname Artist: artistname

Change your exported xml love list from last.fm, into Song: songname Artist: artistname Show Sample Output
This is sample output - yours may be different.
```
Song: Twenty-Three Artist: MC Lars
Song: Listen Close Artist: MC Frontalot
Song: In Arrears Artist: MC Frontalot
Song: Why So Nerdcore Artist: MC GoblinMajick
```
0

cat username_lovedtracks.xspf |perl -pe "s/.*<title>(.*)<\/title><creator>(.*)<\/creator>.*/Song: \1 Artist: \2/gi"> titles

dustylc · 2011-04-07 09:02:11 3
find multiple files in directory and perform search and replace on each of them
This is sample output - yours may be different.
0

files=$(find /dir/file -name *.txt -exec grep -l a {} \;) && perl -p -i -e 's/old/new/g;' $files

highpointe · 2011-04-15 20:32:43 3
find and delete empty directories recursively
This is sample output - yours may be different.
0

perl -MFile::Find -e"finddepth(sub{rmdir},'.')"

igorfu · 2011-05-23 08:45:59 4
Find C/C++ source code comments

more idiomatic version of the same, using the flip-flop-operator; also printing lines with '//'-style comments
This is sample output - yours may be different.
0

perl -ne 'print if m{\Q/*\E}x .. m{\Q*/\E}x or m{\/\/}x' *.c

dbr · 2011-07-12 04:41:49 89
Find all e-mails older than 7 days in the queue and delete them

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.
This is sample output - yours may be different.
0

find /var/spool/mqueue -type f -mtime +7 | perl -lne unlink

mengesb · 2011-08-19 15:22:02 4
Print repeating CSV values on new lines - normalize repeating fields

Lets say you have a file with the following layout: LINUX,DIR,FILE1,FILE2,FILE3 You want the file to look like this: LINUX,DIR,FILE1 LINUX,DIR,FILE2 LINUX,DIR,FILE3 This perl command does it for you. Show Sample Output
This is sample output - yours may be different.
```
LINUX,DIR,FILE1
LINUX,DIR,FILE2
LINUX,DIR,FILE3
```
0

echo "LINUX,DIR,FILE1,FILE2,FILE3" | perl -aF, -nle 'my ($fld1, $fld2, @fields) = @F; while(@fields) { print join ",", $fld1, $fld2, splice(@fields, 0, 1) }'

mindrape · 2011-08-22 18:27:12 4
Generate an XKCD #936 style 4 word password

Before running, do: curl -sO http://world.std.com/%7Ereinhold/diceware.wordlist.asc Show Sample Output
This is sample output - yours may be different.
```
snapcodonmarshstink
```
0

perl -F'\s+' -anE 'push @w,$F[1];END{$r.=splice @w,rand @w,1 for(1..4);say $r}' diceware.wordlist.asc

zedlopez · 2011-08-24 18:50:16 3
format txt as table not joining empty columns adding header with column numbers

This version now adds a header with consecutive numbering. Show Sample Output
This is sample output - yours may be different.
```
cat file.csv
column_a;column_b;column_c
a;b;c
;b;c
a;b;

cat file.csv | perl -pe 'if($. == 1) {@h = split(/;/); $i = 1 ; map { $_ = $i; $i++ } @h; print join(" ;", @h) , "\n"} ; s/(^|;);/$1 ;/g' | column -ts\;
1         2         3
column_a  column_b  column_c
a         b         c
          b         c
a         b
```
0

cat file.csv | perl -pe 'if($. == 1) {@h = split(/;/); $i = 1 ; map { $_ = $i; $i++ } @h; print join(" ;", @h) , "\n"} ; s/(^|;);/$1 ;/g' | column -ts\; | less -S

bashrc · 2011-08-31 12:52:02 4
See your current RAM frequency
This is sample output - yours may be different.
0

/usr/sbin/dmidecode | perl -lne 'print $1 if /Current\s+Speed:\s+(\d+\s+MHz)/'

dbbolton · 2011-09-14 17:32:22 3
Find directories with lots of files in them

Find which directories on your system contain a lot of files. Edit: much shorter and betterer with -n switch. Show Sample Output
This is sample output - yours may be different.
```
2958	/var/www/vhosts/example.com/dir1
2259	/usr/share/man/man3
1283	/var/www/vhosts/example.com/dir2
1124	/usr/share/man/man3p
1091	/usr/share/man/man1
861	/var/www/vhosts/example.com/dir3
763	/usr/bin
717	/var/www/vhosts/example.com/dir4
```
0

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

tamouse · 2011-09-14 19:41:19 3
oneline REPL for perl with warnings and readline support
This is sample output - yours may be different.
0

perl -MTerm::ReadLine -wde'print "TheAnswer=42\n"'

e7__7dal · 2011-09-15 09:44:38 3
speak a chat log file while it's running

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.
This is sample output - yours may be different.
0

tail -f LOGFILE | perl -ne '`say "$_"`;'

tamouse · 2011-09-16 05:33:22 5
Multiple Perl Search/Replace from a file

with a semicolon text file map, apply multiple replace to a single file Show Sample Output
This is sample output - yours may be different.
```
$ cat table-mv.txt
WCFAppRoles;AsAppRoles
WCFDBError;AsDBErrors
WCFFunctions;AsFunctions


$ cat table-mv.txt | perl -pe 's{([^;]+);([^;]+)}{tbl$1/tbl$2}' | perl -pe 's{(\S+)}{perl -i -pe #s/$1/g# xxx.sql}' |  tr "#" "\'"


perl -i -pe 's/tblWCFAppRoles/tblAsAppRoles/g' xxx.sql
perl -i -pe 's/tblWCFDBError/tblAsDBErrors/g' xxx.sql
perl -i -pe 's/tblWCFFunctions/tblAsFunctions/g' xxx.sql
```
0

cat table-mv.txt | perl -pe 's{([^;]+);([^;]+)}{tbl$1/tbl$2}' | perl -pe 's{(\S+)}{perl -i -pe #s/$1/g# xxx.sql}' | tr "#" "\'" | bash

hute37 · 2011-10-05 15:55:34 4
Create a Christmas tree with perl

Require: perl -MCPAN -e 'install Acme::POE::Tree' From: http://www.catonmat.net/blog/christmas-tree-in-the-shell/
This is sample output - yours may be different.
0

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

anhpht · 2011-10-13 10:33:31 4
one-line log format for svn

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!
This is sample output - yours may be different.
0

svn log | perl -pe 's/\n//g => s/^-.*/\n/g'

dbr · 2011-10-20 01:20:52 3
display list of files in a directory sorted by amount of lines different with original.txt.
This is sample output - yours may be different.
0

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"}'

1vq9 · 2011-11-15 06:02:12 3
Print a list of installed Perl modules

Lists all the modules that were installed the "proper way". It also uses Perl 5.10(or higher)'s say command for less typing. Show Sample Output
This is sample output - yours may be different.
```
Algorithm::Diff
Algorithm::NaiveBayes
Alien::Judy
Alien::wxWidgets
Any::Moose
App::FatPacker
App::Nopaste
App::cpanminus
App::perlbrew
AppConfig
Archive::Any
Archive::Extract
Archive::Tar
Archive::Zip
Array::Diff
Array::Iterator
Array::RefElem
Async
```
0

perl -MExtUtils::Installed -E 'say for ExtUtils::Installed->new()->modules()'

kimmel · 2011-11-16 17:26:47 4
convert unixtime to human-readable

convert a unix timestamp to a human readable format. Show Sample Output
This is sample output - yours may be different.
```
Fri Feb 13 23:31:30 2009
```
0

perl -le 'print scalar gmtime shift' 1234567890

kimmel · 2011-11-16 18:37:11 5
clean up syntax and de-obfuscate perl script

This will create a new file with proper code formatting and all comments removed.
This is sample output - yours may be different.
0

perl -MO=Deparse filename.pl | perltidy > new.pl

kimmel · 2011-11-16 18:54:30 4
Converts Character Set of Files in a Folder
This is sample output - yours may be different.
0

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

inomas · 2011-12-02 18:03:27 3

List only locally modified files with CVS

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

cvs -Q status | perl -ne 'print if m/^File.+Status: (?!Up-to-date)/ .. m/^=/;'

dexterp · 2011-12-07 00:33:49 4

Decode \x{ABCD}-style Unicode escape sequences

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 Show Sample Output
This is sample output - yours may be different.
```
$ unidecode "\x{1D306}"
&#119558;
$ unidecode "\x{00A9}\x{2122}\x{00AE}"
???
```
0

perl -e "binmode(STDOUT, ':utf8'); print \"$@\""; echo # newline

mathias · 2012-01-02 10:34:51 6
Delimiter Hunting

Here's a perl version that only considers printable characters. Change the regex /[[:print:]]/ to look for different sets of delimiter characters.
This is sample output - yours may be different.
0

perl -e '$f = join("", <>); for (0..127) {$_ = chr($_); if (/[[:print:]]/) {print if index($f, $_) < 0}} print "\n"'

putnamhill · 2012-01-05 23:38:06 25
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Write comments to your history.

A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Convert seconds to [DD:][HH:]MM:SS

Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Set laptop display brightness

Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Download all manuals RedHat 7 (CentOS/Fedora) with one command in Linux

Convert seconds to [DD:][HH:]MM:SS

vi keybindings with info

Info has some of the worst keybindings I've ever seen. Being a vim user, I attribute that to emacs influence. Use the --vi-keys option to use some of the vi keybindings, although this won't change all the keybindings. Use the "infokey" program to have more control over info keybindings.

List complete size of directories (do not consider hidden directories)

why make it complicated ? : ] -------------------- I just noticed someone else has posted this on this site before me (sorry I am now a duplicate :/) http://www.commandlinefu.com/commands/view/4313

Show the command line for a PID, converting nulls to spaces and a newline

Delete all local git branches that have been merged

This checks if the branch has been merged with master and then will delete the ones that have been. Keeps your local git repo nice and clean from all the branches.

Get last sleep time on a Mac

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Commands using perl (369)

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