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 1218
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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Find the package that installed a command

Ultimate current directory usage command

Based on the MrMerry one, just add some visuals to differentiate files and directories

Create a visually twisted effect by alternating the direction of the "staples" effect vertically. The effect is achieved by moving odd-numbered lines from right to left and even-numbered lines from left to right.

The effect is achieved by moving odd-numbered lines from right to left and even-numbered lines from left to right. For odd-numbered lines (with an index j), the ((j + i) % 2 == 0) condition is satisfied. In this case, the line width is set to i, resulting in the line moving from left to right. For even-numbered lines, the ((j + i) % 2 == 0) condition is not satisfied. The line width is set to $(tput cols) - i, causing the line to move from right to left. This alternating direction of movement creates a twisted visual effect as the lines appear to move in opposite directions. The code runs in a continuous loop, repeatedly updating the lines with changing background colors. There is a slight pause of 0.05 seconds between each iteration to control the speed of the animation.

List all information about all files (in current dir)

This is a funny usage of the traditional command ls. It could be basically simplified as: $ ls -a -l Duplicating arguments is permitted: $ ls -a -l -l And this markup could be shortened as: $ ls -al Extra note: To view filesizes like a pro, pray for your God: $ ls -allah

Sharing file through http 80 port

From the other machine open a web navigator and go to ip from the machine who launch netcat, http://ip-address/ If you have some web server listening at 80 port then you would need stop them or select another port before launch net cat ;-) * You need netcat tool installed

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" }

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

Based on capsule8 agent examples, not rigorously tested

Set laptop display brightness

Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Show Directories in the PATH Which does NOT Exist

Exclude inserting a table from a sql import

Starting with a large MySQL dump file (*.sql) remove any lines that have inserts for the specified table. Sometimes one or two tables are very large and uneeded, eg. log tables. To exclude multiple tables you can get fancy with sed, or just run the command again on subsequently generated files.

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Commands tagged perl (190)

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