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Commands using perl from sorted by
Terminal - Commands using perl - 342 results
find . | perl -wne 'chomp; print qq|<img src="$_" title="$_" /><br />| if /\.(jpg|gif|png)$/;'> gallery.html
2010-07-04 01:43:50
User: spotrick
Functions: find perl
1

This includes a title attribute so you can see the file name by hovering over an image. Also will hoover up any image format - jpg, gif and png.

ifconfig eth0 | perl -ne "print if m/inet addr:((\d+\.){3})+/" | sed "s/inet addr//" | sed "s/Bcast//" |awk -F: '{print $2}'
2010-06-26 12:07:15
User: aceiro
Functions: awk ifconfig perl sed
0

only output the ip addres. I put double pipe with sed because not parse with operator OR (|) in redex.

ifconfig eth0 | perl -ne 'print $1 if m/addr:((?:\d+\.){3}\d+)/'
for pid in `screen -ls | grep -v $STY | grep tached | awk '{print $1;}' | perl -nle '$_ =~ /^(\d+)/; print $1;'`; do screen -x $pid; done
2010-06-22 23:06:31
User: tmsh
Functions: awk grep perl screen
0

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'

perl -p -e 's/^([0-9]*)/"[".localtime($1)."]"/e' < /var/log/squid/access.log
2010-06-22 08:42:40
User: KoRoVaMiLK
Functions: perl
1

On-the-fly conversion of Unix Time to human-readable in Squid's access.log

perl -MNet::Twitter -e '$nt = Net::Twitter->new(traits => [qw/API::REST/], username => "YOUR USERNAME", password => "YOUR PASSWORD"); $ud = $nt->update("YOUR TWEET");'
2010-06-16 19:46:05
User: dbbolton
Functions: perl
2

Requires Net::Twitter. Just replace the double quoted strings with the appropriate info.

git log -p -z | perl -ln0e 'print if /[+-].*searchedstring/'
perl -e 'chomp($k=`uname -r`); for (</boot/vm*>) {s/^.*vmlinuz-($k)?//; $l.="linux-image-$_ ";} system "aptitude remove $l";'
perl -e 'system @ARGV, <STDIN>' ssh host -l user < cmd.txt
2010-06-04 17:27:20
User: recursiverse
Functions: host perl ssh
0

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.

NFSPATH=/mountpoint TIMEOUT=5; perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $NFSPATH" || (umount -fl $NFSPATH; mount $NFSPATH)
2010-06-04 07:59:00
User: keymon
Functions: mount perl umount
8

Based on the execute with timeout command in this site.

A more complex script:

#!/bin/sh

# This script will check the avaliability of a list of NFS mount point,

# forcing a remount of those that do not respond in 5 seconds.

#

# It basically does this:

# NFSPATH=/mountpoint TIMEOUT=5; perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $NFSPATH" || (umount -fl $NFSPATH; mount $NFSPATH)

#

TIMEOUT=5

SCRIPT_NAME=$(basename $0)

for i in $@; do

echo "Checking $i..."

if ! perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $i" > /dev/null 2>&1; then

echo "$SCRIPT_NAME: $i is failing with retcode $?."1>&2

echo "$SCRIPT_NAME: Submmiting umount -fl $i" 1>&2

umount -fl $i;

echo "$SCRIPT_NAME: Submmiting mount $i" 1>&2

mount $i;

fi

done

NFSPATH=/mountpoint TIMEOUT=5; perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $NFSPATH" || (umount -fl $NFSPATH; mount $NFSPATH)
2010-06-04 07:58:53
User: keymon
Functions: mount perl umount
-1

Based on the execute with timeout command in this site.

A more complex script:

#!/bin/sh

# This script will check the avaliability of a list of NFS mount point,

# forcing a remount of those that do not respond in 5 seconds.

#

# It basically does this:

# NFSPATH=/mountpoint TIMEOUT=5; perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $NFSPATH" || (umount -fl $NFSPATH; mount $NFSPATH)

#

TIMEOUT=5

SCRIPT_NAME=$(basename $0)

for i in $@; do

echo "Checking $i..."

if ! perl -e "alarm $TIMEOUT; exec @ARGV" "test -d $i" > /dev/null 2>&1; then

echo "$SCRIPT_NAME: $i is failing with retcode $?."1>&2

echo "$SCRIPT_NAME: Submmiting umount -fl $i" 1>&2

umount -fl $i;

echo "$SCRIPT_NAME: Submmiting mount $i" 1>&2

mount $i;

fi

done

for code in $(find . -type f -name '*.p[ml]'); do perl -c "$code"; done
2010-05-29 23:26:40
User: udog
Functions: find perl
0

Finds all *.p[ml]-files and runs a perl -c on them, checking whether Perl thinks they are syntactically correct

perl -e 'foreach (@ARGV) {@T=stat($_); print localtime($T[8])." - ".$_."\n"}'
perl -e '@F = `ls -1`;while (<@F>){@T = stat($_);print "$_ = " . localtime($T[8]) . "\n";}'
2010-05-20 15:02:51
User: hckhckhck
Functions: perl
0

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.

perl -ne '$w = length if (length > $w); END {print "$w\n"}' *.cpp
perl -ne 'push(@w, length); END {printf "%0d\n" , (sort({$b <=> $a} @w))[0]}' *.cpp
2010-05-11 19:46:37
User: asolkar
Functions: perl
-1

Find the length of the longest line of code in your files.

perl -MDigest::SHA -e 'print substr( Digest::SHA::sha256_base64( time() ), 0, $ARGV[0] ) . "\n"' <length>
2010-04-30 21:45:46
User: udog
Functions: perl
1

Of course you will have to install Digest::SHA and perl before this will work :)

Maximum length is 43 for SHA256. If you need more, use SHA512 or the hexadecimal form: sha256_hex()

lynx -source http://www.lipsum.com/feed/xml?amount=3|perl -p -i -e 's/\n/\n\n/g'|sed -n '/<lipsum>/,/<\/lipsum>/p'|sed -e 's/<[^>]*>//g'
2010-04-26 17:26:44
User: houghi
Functions: perl sed
5

This will generate 3 paragraphs with random text. Change the 3 to any number.

echo $ascii | perl -ne 'printf "%x", ord for split //'
echo $ascii | perl -ne 'printf ("%x", ord($1)) while(/(.)/g); print "\n";'
echo $hex | perl -pe 's/(..)/chr(hex($1))/ge'
perl -i -pe 's/\r/\n/g' file
history | perl -F"\||<\(|;|\`|\\$\(" -alne 'foreach (@F) { print $1 if /\b((?!do)[a-z]+)\b/i }' | sort | uniq -c | sort -nr | head
2010-04-08 13:46:09
User: alperyilmaz
Functions: perl sort uniq
4

Most of the "most used commands" approaches does not consider pipes and other complexities.

This approach considers pipes, process substitution by backticks or $() and multiple commands separated by ;

Perl regular expression breaks up each line using | or < ( or ; or ` or $( and picks the first word (excluding "do" in case of for loops)

note: if you are using lots of perl one-liners, the perl commands will be counted as well in this approach, since semicolon is used as a separator

find ./ -iname "*.djvu" -execdir perl -e '@s=`djvutxt \"$ARGV[0]\"\|grep -c Berlekamp`; chomp @s; print $s[0]; print " $ARGV[0]\n"' '{}' \;|sort -n
2010-04-07 11:15:26
Functions: find grep perl sort
0

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.

perl -MStatistics::Descriptive -alne 'my $stat = Statistics::Descriptive::Full->new; $stat->add_data(@F[1..4]); print $stat->variance' filename
2010-04-02 21:16:12
User: alperyilmaz
Functions: perl
1

In this example, file contains five columns where first column is text. Variance is calculated for columns 2 - 5 by using perl module Statistics::Descriptive. There are many more statistical functions available in the module.