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Functions

Commands using perl from sorted by
Terminal - Commands using perl - 345 results
#(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
2
Up
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Apache CLF access log format to CSV converter

- 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

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Tags: perl, file sizes one line
1
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One line Perl Script to determine the largest file sizes on a Linux Server

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

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useradd -m -p $(perl -e'print crypt("passwordscelta", "stigghiola")') user
2012-02-06 19:53:01
User: 0disse0
Functions: perl useradd
1
Up
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Create new user with home dir and given password

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)

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perl -i -ne 'print if $. == 3..5' <filename>
2012-01-27 23:15:10
User: bashrc
Functions: perl
Tags: bash vi
3
Up
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Remove a range of lines from a file
Show sample output | Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
genRandomText() { perl -e '$n=shift; print chr(int(rand(26)) + 97) for 1..$n; print "\n"' $1;}
2012-01-21 00:21:20
User: putnamhill
Functions: perl
Tags: perl random for loop
-1
Up
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Generate Random Text based on Length

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

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
perl -p -i -e 's/.*\n//g if $.==2' ~/.ssh/known_hosts
2012-01-17 14:11:03
User: meappy
Functions: perl
Tags: ssh perl known_hosts
-1
Up
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Remove a line from a file using sed (useful for updating known SSH server keys when they change)

Easily removes line #2 in ~/.ssh/known_hosts.

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perl -le 'print$_%3?$_%5?$_:"Buzz":$_%5?"Fizz":"FizzBuzz"for 1..100'
2012-01-10 13:10:30
User: depesz
Functions: perl
Tags: perl fizzbuzz
2
Up
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FizzBuzz One-liner
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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
0
Up
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Delimiter Hunting

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.

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find . -type f|perl -lne [email protected]=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
-2
Up
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find the biggest files recursively, no matter how many

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.

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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
0
Up
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Delimiter Hunting

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

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perl -e "binmode(STDOUT, ':utf8'); print \"$@\""; echo # newline
2012-01-02 10:34:51
User: mathias
Functions: echo perl
Tags: perl ascii escape unicode escape sequence characters
0
Up
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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

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perl -ne 's/\^.{1,7}?m//g;print'
2012-01-02 01:32:33
User: Tracerneo
Functions: perl
Tags: perl regex colors
-1
Up
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Remove color codes (special characters) with perl

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]).

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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
0
Up
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List only locally modified files with CVS

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

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find . -iregex ".+\.\(c\|cpp\|h\)" | xargs -I{} perl -e "system(\"iconv -f SHIFT_JIS -t UTF-8 {} > temp; mv temp {} \");" ;
2011-12-02 18:03:27
User: inomas
Functions: find perl xargs
0
Up
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Converts Character Set of Files in a Folder
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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
Tags: perl lsmod dot modules
35
Up
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Draw kernel module dependancy graph.

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

Comments (20) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
perl -MO=Deparse filename.pl | perltidy > new.pl
2011-11-16 18:54:30
User: kimmel
Functions: perl
Tags: perl oneliner beautify
0
Up
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clean up syntax and de-obfuscate perl script

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

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
perl -le 'print scalar gmtime shift' 1234567890
2011-11-16 18:37:11
User: kimmel
Functions: perl
Tags: Date manipulation perl oneliner epoch
0
Up
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convert unixtime to human-readable

convert a unix timestamp to a human readable format.

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perl -MExtUtils::Installed -E 'say for ExtUtils::Installed->new()->modules()'
2011-11-16 17:26:47
User: kimmel
Functions: perl
Tags: perl oneliner
0
Up
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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.

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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"}'
2011-11-15 06:02:12
User: 1vq9
Functions: diff echo ls perl sort wc
0
Up
Down
display list of files in a directory sorted by amount of lines different with original.txt.
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perl -ane 'END{printf(" %d %d %d\n", $x, $y, $z)} $x+=1; [email protected]; $z+=length' file.txt
2011-10-24 06:14:02
User: kev
Functions: perl
Tags: perl
1
Up
Down
wc in perl
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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
3
Up
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sort lines by length

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

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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
0
Up
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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!

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svn log | perl -l40pe 's/^-+/\n/'
2011-10-14 16:02:22
User: bazzargh
Functions: perl
Tags: svn perl svn log
1
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one-line log format for svn

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.

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perl -MAcme::POE::Tree -e 'Acme::POE::Tree->new()->run()'
2011-10-13 10:33:31
User: anhpht
Functions: perl
0
Up
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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/

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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
2011-10-05 15:55:34
User: hute37
Functions: cat perl tr
0
Up
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Multiple Perl Search/Replace from a file

with a semicolon text file map, apply multiple replace to a single file

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate