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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Generate a Change Log with git

Generate a changelog between the v1 and v2 tags

Rename .JPG to .jpg recursively

This command is useful for renaming a clipart, pic gallery or your photo collection. It will only change the big caps to small ones (on the extension).

kills rapidly spawning processes that spawn faster than you can repeat the killall command

if you dont want to alias also then you can do killall rapidly_spawning_process ; !! ; !! ; !!

List all symbolic links in current directory

Many competing commands to do this, but since most people want a Long list with Human readable files sizes and want to see All files (including hidden (.*) files) this one wins on simplicity and usefulness. Plus grep is just as, if not more portable than sed or awk, and is more widely understood. :)

pip install into current directory without virtualenv

For subsequent commands in the prefixed path: $ PYTHONPATH=$PWD/lib/python*/site-packages ./bin/pip --version

An alias to re-run last command with sudo. Similar to "sudo !!"

I didn't come up with this myself, but I always add this to my .bash_aliases file. It's essentially the same idea as running "sudo !!" except it's much easier to type. (You can't just alias "sudo !!", it doesn't really work for reasons I don't understand.) "fc" is a shell built-in for editing and re-running previous commands. The -l flag tells it to display the line rather than edit it, and the -n command tells it to omit the line number. -1 tells it to print the previous line. For more detail: $help fc

tail: watch a filelog

-f file(s) to be monitorized -n number of last line to be printed on the screen in this example, the content of two files are displayed

Analyze awk fields

translate and number lines is simpler and you use tr to choose your delimiter (eg for csv files)

display a smiling smiley if the command succeeded and a sad smiley if the command failed

you could save the code between if and fi to a shell script named smiley.sh with the first argument as and then do a smiley.sh to see if the command succeeded. a bit needless but who cares ;)

FAST Search and Replace for Strings in all Files in Directory

I needed a way to search all files in a web directory that contained a certain string, and replace that string with another string. In the example, I am searching for "askapache" and replacing that string with "htaccess". I wanted this to happen as a cron job, and it was important that this happened as fast as possible while at the same time not hogging the CPU since the machine is a server. So this script uses the nice command to run the sh shell with the command, which makes the whole thing run with priority 19, meaning it won't hog CPU processing. And the -P5 option to the xargs command means it will run 5 separate grep and sed processes simultaneously, so this is much much faster than running a single grep or sed. You may want to do -P0 which is unlimited if you aren't worried about too many processes or if you don't have to deal with process killers in the bg. Also, the -m1 command to grep means stop grepping this file for matches after the first match, which also saves time.

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Commands tagged perl (190)

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