Commands using perl sorted by votes

Commands using perl (369)

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Return IP Address

If you are interested in interfaces other than eth0 you will need to change eth0 to your interface name. You could use this mammoth to nab the ip4 addresses of all your interfaces perl -e '@_=`ifconfig -a`; sort(@_); foreach(@_) { /(inet addr\:)(\d+.\d+.\d+.\d+ )/; $_=$2; @uniq=grep($_ ne $prev && (($prev) = $_), @_);} print join "\n",@uniq,"\n"; ' it seems silly to have all this code when the following will work fine ifconfig -a | grep "inet " | awk -F":" ' { print $2 } ' | cut -d " " -f1 Show Sample Output
This is sample output - yours may be different.
```
10.10.10.10
```
0

perl -e '$_=`ifconfig eth0`;/\d+.\d+.\d+.\d+ /; print $&,"\n";'

solarislackware · 2009-12-05 14:24:48 33
prints line numbers

No need $_ netp ;)
This is sample output - yours may be different.
0

perl -pe 'print "$. "' <file>

sputnick · 2009-12-08 16:11:51 10
Joke : prints line numbers in a longest way

This is a joke for @putnamhill and @glaudiston I'm pretty sure we can write longer if we want ;)
This is sample output - yours may be different.
0

perl -e 'use strict; use warnings; my $c; my $file = $ARGV[0]; open my $handle, "<", $file or die "$0: $file: $!\n"; while (<$handle>) { print $c++, " " x 5, $_; } close($handle);' <FILE>

sputnick · 2009-12-09 16:07:14 7
Extract all urls from last firefox sessionstore used in a portable way.

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

perl -lne 'print for /url":"\K[^"]+/g' $(ls -t ~/.mozilla/firefox/*/sessionstore.js | sed q)

sputnick · 2009-12-14 00:51:54 2
Randomize lines (opposite of | sort)

print the lines of a file in randomized order Show Sample Output
This is sample output - yours may be different.
```
$ perl -wl -e '@f=<>; for $i (0 .. $#f) { $r=int rand ($i+1); @f[$i, $r]=@f[$r,$i] if ($i!=$r); } chomp @f; print join $/, @f;' try.txt
 34
 42
 48
 14
 51
 44
 46
 41
 39
 12
  3
 28
  4
 22
 20
 35
 29
 16
 21
 27
 13
  6
 26
  1
 30
  8
 47
 32
  2
 45
 11
 19
 37
 23
 10
 31
 18
  7
 38
 25
 15
 50
  5
 49
 40
 43
 36
  9
 33
 24
 17
```
0

perl -wl -e '@f=<>; for $i (0 .. $#f) { $r=int rand ($i+1); @f[$i, $r]=@f[$r,$i] if ($i!=$r); } chomp @f; print join $/, @f;' try.txt

JohnGH · 2009-12-21 21:15:55 3
Display the output of a command from the first line until the first instance of a regular expression.

This command line will display the output of , from the first line of output, until the first time it sees a pattern matching . You could specify the regex pattern /^$/ to look for the first blank line, or /^foobar/ to look for the first line that starts with the word foobar.
This is sample output - yours may be different.
0

<your command here> | perl -n -e 'print "$_" if 1 ... /<regex>/;'

SuperFly · 2009-12-22 14:06:41 4
Display the output of a command from the first line until the first instance of a regular expression.

Doesn't display the matching line. If you want that behaviour, you need to add "print && " before the 'exit'.
This is sample output - yours may be different.
0

<command> | perl -pe '/<regex/ && exit;'

intuited · 2009-12-22 15:05:49 3
AIX : reset aixuser password lastupdate to now using perl
This is sample output - yours may be different.
0

perl -e '$now=time; system "chsec -f /etc/security/passwd -s aixuser -a \"lastupdate=$now\""'

snaguber · 2010-03-24 12:54:29 3
Grep through the text of djvu files and format results

Count the occurences of the word 'Berlekamp' in the DJVU files that are in the current directory, printing file names from the one having the least to the most occurences.
This is sample output - yours may be different.
0

find ./ -iname "*.djvu" -execdir perl -e '@s=`djvutxt \"$ARGV[0]\"\|grep -c Berlekamp`; chomp @s; print $s[0]; print " $ARGV[0]\n"' '{}' \;|sort -n

unixmonkey4437 · 2010-04-07 11:15:26 8
Legacy MacOS to Unix text convert using perl
This is sample output - yours may be different.
0

perl -i -pe 's/\r/\n/g' file

octopus · 2010-04-16 13:25:09 4
convert a string of hex characters into ascii chars
This is sample output - yours may be different.
0

echo $hex | perl -pe 's/(..)/chr(hex($1))/ge'

dfaulkner · 2010-04-17 16:24:48 5
Length of longest line of code

More straightforward. Show Sample Output
This is sample output - yours may be different.
```
96
```
0

perl -ne '$w = length if (length > $w); END {print "$w\n"}' *.cpp

asolkar · 2010-05-11 19:53:07 4
Print time and year of file in Solaris (or other Unix ls command that does not have a simple "--full-list")

Solaris 'ls' command does not have a nice '--full-time' arg to make the time show after a year has passed. So I spit this out quick. It hates spaces in file names. Show Sample Output
This is sample output - yours may be different.
```
Test_DR.sh = Mon Jul  6 09:22:35 2009
Test_DR.sh-20080806-hck = Sun Aug 17 13:46:34 2008
Test_DR.sh~ = Sun Aug 17 13:49:59 2008
utk_cod-savesets = Wed Mar 14 11:20:46 2007
utkdc8 = Fri Nov  3 17:18:21 2006
Vics-data = Thu Jan 21 14:30:29 2010
```
0

perl -e '@F = `ls -1`;while (<@F>){@T = stat($_);print "$_ = " . localtime($T[8]) . "\n";}'

hckhckhck · 2010-05-20 15:02:51 5
Print time and year of file in Solaris (or other Unix ls command that does not have a simple
This is sample output - yours may be different.
0

perl -e 'foreach (@ARGV) {@T=stat($_); print localtime($T[8])." - ".$_."\n"}'

putnamhill · 2010-05-20 16:19:17 4
run complex remote shell cmds over ssh, without escaping quotes

I was tired of the endless quoting, unquoting, re-quoting, and escaping characters that left me with working, but barely comprehensible shell one-liners. It can be really frustrating, especially if the local and remote shells differ and have their own escaping and quoting rules. I decided to try a different approach and ended up with this.
This is sample output - yours may be different.
0

perl -e 'system @ARGV, <STDIN>' ssh host -l user < cmd.txt

recursiverse · 2010-06-04 17:27:20 3
Iterate through screens

Personally, I save this in a one line script called ~/bin/sci: #!/bin/bash for pid in `screen -ls | grep -v $STY | grep tached | awk '{print $1;}' | perl -nle '$_ =~ /^(\d+)/; print $1;'`; do screen -x $pid; done I also use: alias scx='screen -x' alias scl='screen -ls | grep -v $STY'
This is sample output - yours may be different.
0

for pid in `screen -ls | grep -v $STY | grep tached | awk '{print $1;}' | perl -nle '$_ =~ /^(\d+)/; print $1;'`; do screen -x $pid; done

tmsh · 2010-06-22 23:06:31 29
Get IPv4 of eth0 for use with scripts

only output the ip addres. I put double pipe with sed because not parse with operator OR (|) in redex. Show Sample Output
This is sample output - yours may be different.
```
192.168.1.102
```
0

ifconfig eth0 | perl -ne "print if m/inet addr:((\d+\.){3})+/" | sed "s/inet addr//" | sed "s/Bcast//" |awk -F: '{print $2}'

aceiro · 2010-06-26 12:07:15 4
Show full path followed by a command

This will show you any links that a command follows (unlike 'file -L'), as well as the ultimate binary or script. Put the name of the command at the very end; this will be passed to perl as the first argument. For obvious reasons, this doesn't work with aliases or functions. Show Sample Output
This is sample output - yours may be different.
```
$ perl -le 'chomp($w=`which $ARGV[0]`);$_=`file $w`;while(/link\b/){chomp($_=(split/`/,$_)[1]);chop$_;$w.=" -> $_";$_=`file $_`;}print "\n$w";' vi          

/usr/bin/vi -> /etc/alternatives/vi -> /usr/bin/vim.gtk
```
0

perl -le 'chomp($w=`which $ARGV[0]`);$_=`file $w`;while(/link\b/){chomp($_=(split/`/,$_)[1]);chop$_;$w.=" -> $_";$_=`file $_`;}print "\n$w";' COMMAND_NAME

dbbolton · 2010-07-30 19:26:35 5
Create new user with home directory and given password

Function: char * crypt (const char *key, const char *salt) 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. The salt parameter does two things. Firstly, it selects which algorithm is used, the MD5-based one or the DES-based one. Secondly, it makes life harder for someone trying to guess passwords against a file containing many passwords; without a salt, an intruder can make a guess, run crypt on it once, and compare the result with all the passwords. With a salt, the intruder must run crypt once for each different salt. For the MD5-based algorithm, the salt should consist of the string $1$, followed by up to 8 characters, terminated by either another $ or the end of the string. The result of crypt will be the salt, followed by a $ if the salt didn't end with one, followed by 22 characters from the alphabet ./0-9A-Za-z, up to 34 characters total. Every character in the key is significant. For the DES-based algorithm, the salt should consist of two characters from the alphabet ./0-9A-Za-z, and the result of crypt will be those two characters followed by 11 more from the same alphabet, 13 in total. Only the first 8 characters in the key are significant. Show Sample Output
This is sample output - yours may be different.
```
root# useradd -m -p $(perl -e'print crypt("foo", "aa")') foo
user$ su - foo
Password: foo
foo$ ^D
root# userdel -r foo
```
0

useradd -m -p $(perl -e'print crypt("pass", "mb")') user

mariusbutuc · 2010-09-03 19:00:56 6
Show the changed files in your GIT repo

Parse the output of git status. Once the line '# Changed but not updated:' has passed print every last part of the line if it exists on disk.
This is sample output - yours may be different.
0

git status | perl -F'\s' -nale 'BEGIN { $a = 0 }; $a = 1 if $_ =~ /changed but not updated/i; print $F[-1] if ( $a && -f $F[-1] )'

coffeeaddict_nl · 2010-10-15 07:58:14 4
recursive transform all contents of files to lowercase
This is sample output - yours may be different.
0

perl -e "tr/[A-Z]/[a-z]/;" -pi.save $(find . -type f)

miccaman · 2010-11-25 12:48:39 4
find an unused unprivileged TCP port

perl-based version
This is sample output - yours may be different.
0

netstat -atn | perl -ane 'if ( $F[3] =~ /(\d+)$/ ) { $x{$1}=1 } END{ print( (grep {!$x{$_}} 32768..61000)[0] . "\n" )}'

depesz · 2010-12-15 09:25:52 4
Unix timestamp Solaris
This is sample output - yours may be different.
0

perl -le 'print time()'

depesz · 2011-01-12 16:45:23 3
Perl One Liner to Generate a Random IP Address
This is sample output - yours may be different.
0

perl -e 'printf join ".", map int rand 256, 1 .. 4;'

gml · 2011-01-16 02:15:29 6
Perl One Liner to Generate a Random IP Address
This is sample output - yours may be different.
0

perl -le '$,=".";print map int rand 256,1..4'

depesz · 2011-01-16 16:56:44 3
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Query ip pools based on successive netnames via whois

Useful if you f.i. want to block/allow all connections from a certain provider which uses successive netnames for his ip blocks. In this example I used the german Deutsche Telekom which has DTAG-DIAL followed by a number as netname for the dial in pools. There are - as always ;) - different ways to do this. If you have seq available you can use $ net=DTAG-DIAL ; for i in `seq 1 30`; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; done or without seq you can use bash brace expansion $ net=DTAG-DIAL ; for i in {1..30}; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; done or if you like while better than for use something like $ net=DTAG-DIAL ; i=1 ; while true ; do whois -h whois.ripe.net $net$i | grep '^inetnum:' | sed "s;^.*:;$net$i;" ; test $i = 30 && break ; i=$(expr $i + 1) ; done and so on.

Display all shell functions set in the current shell environment

Uses the shell builtin `declare` with the '-f' flag to output only functions to grep out only the function names. You can use it as an alias or function like so: alias shfunctions="builtin declare -f | command grep --color=never -E '^[a-zA-Z_]+\ '" shfunctions () { builtin declare -f | command grep --color=never -E '^[a-zA-Z_]+\ '; }

Find dead symbolic links

-L tells find to follow symbolic links, so -type l will only return links it can't follow (i.e., those that are broken).

Print trending topics on Twitter

Show line numbers in a text file

Find usb device in realtime

Using this command you can track a moment when usb device was attached.

Basic sed usage with xargs to refactor a node.js depdendency

Install pip with Proxy

Installs pip packages defining a proxy

Sorts and compare 2 files line by line

vi a remote file

notice the double slash

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Commands using perl (369)

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