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 1308
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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Awk: Perform a rolling average on a column of data

Sometimes jittery data hides trends, performing a rolling average can give a clearer view.

Find files in multiple TAR files

A quick find command to identify all TAR files in a given path, extract a list of files contained within the tar, then search for a given string in the filelist. Returns to the user as a list of TAR files found (enclosed in []) followed by any matching files that exist in that archive. TAR can easily be swapped for JAR if required.

Change host name

With sed you can replace strings on the fly.

Dump a web page

Useful to browse dangerous web sites.

run complex remote shell cmds over ssh, without escaping quotes

It executes commands as arguments to ssh, avoiding problematic shell expansions, without the need of writing the commands in question to a temporary file, just reading them from STDIN.

Simple addicting bash game.

Really bored during class so I made this... Basically, you hold period (or whatever) and hit enter after a second and you need to make the next line of periods the same length as the previous line... My record was 5 lines of the same length. It's best if you do it one handed with your pointer on period and ring on enter.

use jq to validate and pretty-print json output

the `jq` tool can also be used do validate json files and pretty print output `cat file.json | jq` available on several platforms, including newer debian-based systems via `#sudo apt install jq`, mac via `brew install jq`, and from source https://stedolan.github.io/jq/download/

Create a tar archive using xz compression

compress directory archive with xz compression, if tar doesn't have the -J option (OSX tar doesn't have -J)

Delete an IPtable rules based on row number

Calculating series with awk: add numbers from 1 to 100

"seq 100" outputs 1,2,..,100, separated by newlines. awk adds them up and displays the sum. "seq 1 2 11" outputs 1,3,..,11. Variations: 1+3+...+(2n-1) = n^2 $ seq 1 2 19 | awk '{sum+=$1} END {print sum}' # displays 100 1/2 + 1/4 + ... = 1 $ seq 10 | awk '{sum+=1/(2**$1)} END {print sum}' # displays 0.999023

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Commands tagged perl (190)

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