Commands using perl sorted by votes

Commands using perl (369)

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Replace DOS character ^M with newline using perl inline replace.

Replace DOS character ^M with newline using perl inline replace.
This is sample output - yours may be different.
-1

perl -pi -e "s/\r/\n/g" <file>

din7 · 2010-07-29 16:07:36 4
calculate in commandline with perl
This is sample output - yours may be different.
-1

perl -e 'print 1+1 ."\n";'

stubby · 2010-08-08 23:19:10 3
Perl One Liner to Generate a Random IP Address

Show Sample Output
This is sample output - yours may be different.
```
108.134.80.236
```
-1

perl -e 'printf "%vd\n",pack "N",rand 256**4'

seungwon · 2011-01-18 06:10:18 3
Print just line 4 from a textfile

Perl version - just for completeness sake ;)
This is sample output - yours may be different.
-1

perl -ne '$. == 4 && print && exit'

bashrc · 2011-09-05 21:52:16 3
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]).
This is sample output - yours may be different.
-1

perl -ne 's/\^.{1,7}?m//g;print'

Tracerneo · 2012-01-02 01:32:33 6
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. Show Sample Output
This is sample output - yours may be different.
-1

perl -p -i -e 's/.*\n//g if $.==2' ~/.ssh/known_hosts

meappy · 2012-01-17 14:11:03 3
Generate Random Text based on Length

If you don't have seq, you can use perl.
This is sample output - yours may be different.
-1

genRandomText() { perl -e '$n=shift; print chr(int(rand(26)) + 97) for 1..$n; print "\n"' $1;}

putnamhill · 2012-01-21 00:21:20 3
Per country GET report, based on access log. Easy to transform to unique IP

Per country GET report, based on access log. Easy to transform to unique IP Show Sample Output
This is sample output - yours may be different.
```
     71 , Poland
    116 , France
    300 , United States
   2426 , Spain
```
-1

cat /var/log/nginx/access.log | grep -oe '^[0-9.]\+' | perl -ne 'system("geoiplookup $_")' | grep -v found | grep -oe ', [A-Za-z ]\+$' | sort | uniq -c | sort -n

theist · 2012-05-08 13:28:25 3
Print environment information.

Show Sample Output
This is sample output - yours may be different.
```
user@server:~$ perl -e 'print "$_=$ENV{$_}\n" for keys %ENV'
HOME=/home/user
LESS=-R
LC_ALL=de_DE.utf8
EDITOR=/usr/bin/vim
...
```
-1

perl -e 'print "$_=$ENV{$_}\n" for keys %ENV'

sgikas · 2012-11-12 13:14:28 4
Find out if a module is installed in perl

Will check if the given module is installed in the @INC. It will print the path and return 0 if found, or 1 otherwise. Based on script from SharpyWarpy in http://www.linuxquestions.org/questions/linux-general-1/how-to-list-all-installed-perl-modules-216603/ Show Sample Output
This is sample output - yours may be different.
```
/usr/local/share/perl5/Collectd/Plugins/Graphite.pm
```
-1

perl -MFile::Find=find -MFile::Spec::Functions -Tlwe '$found=1; find { wanted => sub { if (/$ARGV[0]\.pm\z/) { print canonpath $_; $found=0; } }, no_chdir => 1 }, @INC; exit $found;' Collectd/Plugins/Graphite

keymon · 2013-01-11 11:01:46 5

Find out if a module is installed in perl (and what version)

This attempts to load a Perl Module (-M flag) and use version 9999, since no module has a version this high, Perl exits either a) telling you the version of the module installed or b) tells you it can't find the module. Show Sample Output

-1

perl -MModule::Name\ 9999 -e 1

three18ti · 2013-01-15 22:51:39 4

Display Spinner while waiting for some process to finish

Replace 'sleep 10' with the command to wait for Show Sample Output
This is sample output - yours may be different.
```
\oOooo
```
-1

sleep 10 & perl -e '$|=@s=qw(-Ooooo \oOooo |ooOoo /oooOo -ooooO \oooOo |ooOoo /oOooo);while(kill 0,'$!'){ print "\r",$s[$t++%($#s+1)];select(undef,undef,undef,0.2);}'

unixmonkey74668 · 2015-05-09 10:00:35 9
shell function to create an 'invisible regex' that won't show up when grepping the output from 'ps'

Note that `grep "$(ir foo)"` really doesn't save any typing, but wrapping this inside a second shell function will: psg() { grep "$(ir \"$@\")" ;} Show Sample Output
This is sample output - yours may be different.
```
$ ir foo
[f]oo

$ ps aux | grep "$(ir foo)"
[returns nothing]
```
-1

ir() { perl -pne 's/(.)(.*)/\[\1]\2/' <<< "$@" ;}

bartonski · 2015-07-25 14:13:33 12
rename all images in folder with original date time from exif data

for filename multilingual (ex.japanese, chinese, ...etc)
This is sample output - yours may be different.
-1

c=1; for i in *; do identify -verbose $i | perl -ane 'if(/exif:DateTimeOriginal:/){print "@F[1,2] "}'; ls -i $i; done | sort | perl -ane 'print "@F[2]\n"' | while read j; do find -inum $j | xargs -iX cp X NEW_`printf %02d $c`.jpg; cnt=`expr $c + 1`; done

huzioka · 2015-09-22 19:06:43 11
Binary digits Matrix effect
This is sample output - yours may be different.
-1

perl -e 'use Term::ANSIColor;$|++; while (1) { print color("green")," " x (rand(35) + 1), int(rand(2)), color("reset") }'

mvrpl · 2017-04-26 14:05:48 20
Inserting a decimal every third digit

self explanatory see sample output Show Sample Output
This is sample output - yours may be different.
```
# echo "1234435324523443212343241" | perl -lpe'1 while s/^([-+]?\d+)(\d{3})/$1.$2/'
1.234.435.324.523.443.212.343.241
```
-2

perl -lpe'1 while s/^([-+]?\d+)(\d{3})/$1.$2/'

sil · 2009-02-18 21:54:22 6
Convert files with CR-terminated lines (as created by Mac OS X programs) into NL-terminated lines suitable for Unix programs

Many Mac OS X programs, especially those in Microsoft:Office, create ASCII files with lines terminated by CRs (carriage returns). Most Unix programs expect lines separated by NLs (newlines). This little command makes it trivial to convert them. Show Sample Output
This is sample output - yours may be different.
```
crtonl mymacfile.csv
```
-2

function crtonl { perl -i -ape 's/\r\n?/\n/g;' $* ; }

totoro · 2009-03-25 20:28:32 10
Not so simple countdown from a given date

An improved version of http://www.commandlinefu.com/commands/view/1772/simple-countdown-from-a-given-date that uses Perl to pretty-print the output. Note that the GNU-style '--no-title' option has been replaced by its one-letter counterpart '-t'. Show Sample Output
This is sample output - yours may be different.
```
4d 23:15:43
```
-2

watch -tn1 'bc<<<"`date -d'\''friday 21:00'\'' +%s`-`date +%s`"|perl -ne'\''@p=gmtime($_);printf("%dd %02d:%02d:%02d\n",@p[7,2,1,0]);'\'

penpen · 2009-03-29 19:53:36 8
Read just the IP address of a device

Found this useful for scripts where I needed to work with the machine's IP. If $DEVICE is not specified, this will return all IPs on the machine. If $DEVICE is set to a network adapter, it will return just that adapter's IP.
This is sample output - yours may be different.
-2

ifconfig $DEVICE | perl -lne '/inet addr:([\d.]+)/ and print $1'

jdob · 2009-07-21 13:48:19 6
Make perl crash

It is not easy to make perl give a segfault, but this does it. This is a known issue but apparently not easy to fix. This is completely useless except for showing people that perl is not bullet-proof. Show Sample Output
This is sample output - yours may be different.
```
Segmentation fault
```
-2

perl -e '$x = []; push @$x, eval { $x = 1; return $x = 1; }'

dstahlke · 2009-10-07 22:42:18 8
Transforms a file to all uppercase.

same, except it works on any OS with Perl installed. DOS, Windose, whatever
This is sample output - yours may be different.
-2

perl -pi -e 's/([[:lower:]]+)/uc $1/gsex' file

linuxrawkstar · 2009-10-08 14:18:50 3
Echo several blank lines

Perl variant of echo several blank lines command
This is sample output - yours may be different.
-2

perl -e 'print "\n"x100'

SunX · 2010-09-07 10:11:10 3
Bulk install

I used this to mass install a lot of perl stuff. Threw it together because I was feeling *especially* lazy. The 'perl' and the 'module' can be replaced with whatever you like.
This is sample output - yours may be different.
-2

apt-cache search perl | grep module | awk '{print $1;}' | xargs sudo apt-get install -y

captwheeto · 2010-11-26 14:00:39 3
Get DELL Warranty Information from support.dell.com

The dates in the output are Start Date, End Date, Days Remaining in warranty, respectively. This will only work if you are running it on a dell machine. You can substitute the dmidecode command with a service tag if you are not using a dell. Also, you have to either allow your user to run sudo dmidecode with no password or run this command as root. Show Sample Output
This is sample output - yours may be different.
```
Product Support for Latitude D820

Your Warranty
Next Business Day Support 4/16/2008 4/16/2010 0
```
-2

curl -Ls "http://support.dell.com/support/DPP/Index.aspx?c=us&cs=08W&l=en&s=biz&ServiceTag=$(dmidecode -s system-serial-number)"|egrep -i '>Your Warranty<|>Product Support for'|html2text -style pretty|egrep -v 'Request|View'|perl -pane 's/^(\s+|\})//g;'

din7 · 2011-02-18 22:29:05 3
Print sorted list of all installed packages (Debian)

A space-padded version: perl -m'AptPkg::Cache' -e '$c=AptPkg::Cache->new; for (keys %$c){ push @a, $_ if $c->{$_}->{'CurrentState'} eq 'Installed';} print "$_ " for sort @a;'
This is sample output - yours may be different.
-2

perl -m'AptPkg::Cache' -le '$c=AptPkg::Cache->new; for (keys %$c){ push @a, $_ if $c->{$_}->{'CurrentState'} eq 'Installed';} print for sort @a;'

dbbolton · 2011-03-14 23:56:43 3
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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" }

Increase SCT of external USB disk enclosure to one hour.

So I had this 2TB Seagate external disk/USB enclosure which by default would spin-down its internal drive (it enters a standby mode) after four minutes of inactivity.. Spinning-up the inactive drive was an annoying delay when accessing files and also it severely interfered with NFS.. SCT stands for "Standby Condition Timer". To completely disable SCT: $ sdparm --clear STANDBY -6 /dev/sdb To return to original (default) SCT settings: $ sdparm -D -p 0x1a -6 /dev/sdb To verify the settings (before and after): $ sdparm -a /dev/sdb No need for vendor-provided MSWIN tools, etc.

force unsupported i386 commands to work on amd64

The above was done using the i386 flashplayer plugin, and was installed on a AMD64 machine running an AMD64 kernel and AMD64 programs. the resulting plugin install ultimately didn't work for swiftfox (but worked for iceweasel) without also covering it with a nspluginwrapper which took a bit of fenangaling to get to work (lots of apt-getting) but it is a nice feature to be able to trick installers that think you need i386 into running on a amd64, or at least attempting to run on amd64. Enjoy

find text in a file

this will find text in the directory you specify and give you line where it appears.

Use ImageMagick to get an image's properties

Generate an XKCD #936 style 4 word password

The improvement of this command over Strawp's original alternative is that you can specify the size of the words, in this particular case words between 3 and 5 character's long. It also excludes words that contain apostrophes, if you'd rather keep those words simply substitue [^'] for .

Change files case, without modify directories, recursively

Change files case, without modify directories, recursively. ... fucking vfat

Rename files in batch

Link a deep tree of files all into on directory

If you want to pull all of the files from a tree that has mixed files and directories containing files, this will link them all into a single directory. Beware of filesystem files-per-directory limits.

View online pdf documents in cli

Probably will not work very well with scanned documents.

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Commands using perl (369)

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