Commands tagged perl sorted by votes

Commands tagged perl (190)

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Get user's full name in Mac OS X
This is sample output - yours may be different.
0

finger $(whoami) | perl -ne '/Name: ([a-zA-Z0-9 ]{1,})/ && print "$1\n"'

zil0g · 2014-09-30 11:37:47 11
Print a row of characters across the terminal
This is sample output - yours may be different.
0

perl -E'say "#" x '$COLUMNS

pung96 · 2015-05-09 13:49:56 9
Wait for file to stop changing

perl version of "Wait for file to stop changing" When "FileName" has not been changed for last 10 seconds, then print "DONE" "10" in "(stat)[10]" means ctime. One have other options like atime, mtime and others. http://perldoc.perl.org/functions/stat.html
This is sample output - yours may be different.
0

echo FileName | perl -nlE'sleep 1 while time-(stat)[10]<10' && echo DONE

pung96 · 2015-05-09 14:58:41 9
drop first column of output by piping to this

drop first column with perl "$#F" means a index of last column(start from 0). One can easily handle range of columns like "[3..6]"
This is sample output - yours may be different.
0

perl -anE'say join "\t",@F[1..$#F]'

pung96 · 2015-05-09 15:11:23 9
List all symbolic links in current directory that matches regexp

If you want to search for all symlinks in current directory AND its subdirectories, make sure you omit the "-maxdepth 1" bit. Also, modify regextype as desired. I DO prefer to AVOID the use of extended regexp whenever possible, because this will usually only give correct results if you use GNU find. Hack a line containing ext-regexp into an HP-UX workstation, and you're in trouble.
This is sample output - yours may be different.
0

find . -maxdepth 1 -type l -regextype posix-basic -regex '.*what[ev]er?.*'

syntaxerror74 · 2015-06-06 16:22:25 9
Print hex codes of a given string

Prints a string as a sequence of hexadecimal values. Output comes in space separated pairs, regardless of ASCII or Unicode characters Show Sample Output
This is sample output - yours may be different.
```
$ hexstring commandlinefu
63 6f 6d 6d 61 6e 64 6c 69 6e 65 66 75
```
0

hexstring () { perl -p -e 's/(.)/sprintf("%02x", ord($1))/eg' << $1 }

hellcode · 2016-05-03 22:44:24 10
Run an interactive program with perl code expansion

Start an interactive program with perl code expansion. Everything between #[ ] is evaluated as perl code. #[ ] tags must not be nested (it wouldn't make sense anyway). Show Sample Output
This is sample output - yours may be different.
```
plexpand sed -s 's/a/x/g'
banana
bxnxnx
b#["an"x2]a
bxnxnx
```
0

plexpand() { mkfifo /tmp/plxpnd; $@ </tmp/plxpnd & perl -p -e '$|=1; s/#\[(.*)\]/eval($1)/ge' >/tmp/plxpnd; rm /tmp/plxpnd; }

hellcode · 2016-05-10 04:49:35 9

perl http get one-liner

HTTP Get, without LWP::Simple Show Sample Output

perl -MLWP::UserAgent -le 'print LWP::UserAgent->new(requests_redirectable => [])->get(shift)->decoded_content()' "http://dazzlepod.com/ip/me.json"

dbiesecke · 2016-06-23 21:12:26 13

Pretty print docker ps command

If you have many port mappings, docker ps output becomes pretty illegible. The ~120 char one-liner changes the output into a more readable list of container! Show Sample Output
This is sample output - yours may be different.
```
$ docker ps [...]

70f949a68c3f               # bold
image:latest
"/start.sh"
8 hours ago
Up 8 hours                 # colorful if up or down
127.0.0.1:9002->9000/tcp
zauberstuhl                # underlined

[...]
```
0

docker ps | perl -ple "s/\$/\n\n/g;s/\s{2,}/\n/g;s/(Up)/\\e\[32m\$1\\e\[0m/g;s/(Down)/\\e\[31m\\e\[5m\$1\\e\[25m\\e\[0m/g;s/^([^\n]+)/\\e\[1m\$1\\e\[0m/g;s/(\w+?)$/\\e\[4m\$1\\e\[24m/g" | more

zauberstuhl · 2017-01-05 02:46:15 14
Get the total length of all video / audio in the current dir (and below) in H:m:s

Uses soxi instead of mplayer
This is sample output - yours may be different.
0

soxi -D * | awk '{SUM += $1} END { printf "%d:%d:%d\n",SUM/3600,SUM%3600/60,SUM%60}'

hufman · 2017-04-08 17:37:03 15
shuffle lines via perl
This is sample output - yours may be different.
0

seq 1 9 | perl -MList::Util=shuffle -e 'print shuffle <>;'

emphazer · 2019-07-03 09:39:08 38
From all PDF files in all subdirectories, extract two metadata fields (here: Creator and Producer) into a CSV table
This is sample output - yours may be different.
0

echo "File;Creator;Producer";find . -name '*.pdf' -print0 | while IFS= read -d $'\0' line;do echo -n "$line;";pdfinfo "$line"|perl -ne 'if(/^(Creator|Producer):\s*(.*)$/){print"$2";if ($1 eq "Producer"){exit}else{print";"}}';echo;done 2>/dev/null

langec · 2020-12-17 21:08:55 1252
Change all instances of a word in all files in the current directory and it's sub-directories

This command will replace all instances of 'foo' with 'bar' in all files in the current working directory and any sub-directories.
This is sample output - yours may be different.
-1

perl -pi -e 's/foo/bar/g' $(grep -rl foo ./*)

dopeman · 2009-03-27 17:21:35 10
regex to match an ip

if you want to only print the IP address from a file. In this case the file will be called "iplist" with a line like "ip address 1.1.1.1" it will only print the "1.1.1.1" portion
This is sample output - yours may be different.
-1

perl -wlne 'print $1 if /(([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5]))/' iplist

salparadise · 2009-09-17 16:14:52 3
Print all members of US House of Representatives

Uses curl to download page of membership of US Congress. Use sed to strip HTML then perl to print a line starting with two tabs (a line with a representative) Show Sample Output
This is sample output - yours may be different.
```
curl "http://www.house.gov/house/MemberWWW.shtml" 2>/dev/null | sed -e :a -e 
  's/<[^>]*>//g;/</N;//ba' | perl -nle 's/^\t\t(.*$)/ $1/ and 
  print;' > DefeatedIn2010.txt

#Fills a file called "DefeatedIn2010.txt" with the name of every member of congress.
```
-1

curl "http://www.house.gov/house/MemberWWW.shtml" 2>/dev/null | sed -e :a -e 's/<[^>]*>//g;/</N;//ba' | perl -nle 's/^\t\t(.*$)/ $1/ and print;'

drewk · 2009-09-24 23:37:36 15
Transforms a file to all uppercase.
This is sample output - yours may be different.
-1

perl -i -ne 'print uc $_' $1

rbs · 2009-10-15 16:59:38 4
Match a URL

don't have to be that complicated
This is sample output - yours may be different.
-1

cho "(Something like http://foo.com/blah_blah)" | awk '{for(i=1;i<=NF;i++){if($i~/^(http|ftp):\/\//)print $i}}'

unixmonkey7109 · 2009-11-28 03:31:41 6
Print the lastest stable version of Perl

This uses wget instead of curl
This is sample output - yours may be different.
-1

wget -q -O - http://www.perl.org/get.html | grep -m1 '\.tar\.gz' | sed 's/.*perl-//; s/\.tar\.gz.*//'

dbbolton · 2011-08-19 23:38:10 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
Show git branches by date - useful for showing active branches

simple table
This is sample output - yours may be different.
-1

for k in `git branch -r|awk '{print $1}'`;do echo -e `git show --pretty=format:"%Cgreen%ci_%C(blue)%c r_%Cred%cn_%Creset" $k|head -n 1`$k;done|sort -r|awk -F"_" '{printf("%s %17s %-22s %s\n",$1,$2,$3,$4)}'

varon · 2012-10-29 12:38:24 6
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 (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

Randomize lines (opposite of | sort)
This is sample output - yours may be different.
-1

ls -1 | xargs ruby -e'puts ARGV.shuffle'

jacaetevha · 2014-01-17 17:42:08 7
‹ First < 5 6 7 8 >

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What is my ip?

Use Perl like grep

Much better alternatives - grep-alikes using perl regexps. With more options, and nicer outputs.

Break lines after, for example 78 characters, but don't break within a word/string

Per default, linux/unix shells are configured with a width of 80 characters. If you like to edit a phrase or string on a line with more than 80 characters it might take long to go there (for example a line with 1000 characters and you like to edit the 98th word which is character 598-603). Maybe you might wish to use 78 characters, because if you forward the text via mail and the text will be quoted (2 extra characters at the beginning to the line "> "), you use 80 characters, otherwise 82, which are lame.

How to get an absolute value

Whenever we are only interested in difference between two numbers and not the positive/negative values we can use this in script.

Get list of servers with a specific port open

Change the -p argument for the port number. See "man nmap" for different ways to specify address ranges.

Detect illegal access to kernel space, potentially useful for Meltdown detection

Based on capsule8 agent examples, not rigorously tested

List your installed Chromium extensions (with url to each page)

Gives you a list for all installed chrome (chromium) extensions with URL to the page of the extension. With this you can easy add a new Bookmark folder called "extensions" add every URL to that folder, so it will be synced and you can access the names from every computer you are logged in. ------------------------------------------------------------------------------------------------------------------ Only tested with chromium, for chrome you maybe have to change the find $PATH.

What is my ip?

copy root to new device

Clone a root partition. The reason for double-mounting the root device is to avoid any filesystem overlay issues. This is particularly important for /dev. Also, note the importance of the trailing slashes on the paths when using rsync (search the man page for "slash" for more details). rsync and bash add several subtle nuances to path handling; using trailing slashes will effectively mean "clone this directory", even when run multiple times. For example: run once to get an initial copy, and then run again in single user mode just before rebooting into the new disk. Using file globs (which miss dot-files) or leaving off the trailing slash with rsync (which will create /mnt/target/root) are traps that are easy to fall into.

get all Google ipv4 subnets for a iptables firewall for example

a bit shorter, parenthesis not needed but added for clarity

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Commands tagged perl (190)

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