Commands using perl sorted by votes

Commands using perl (369)

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List apache2 virtualhosts

Lists virtualhosts currently enabled for apache2, showing the ServerName:port, conf file and DocumentRoot
This is sample output - yours may be different.
4

/usr/sbin/apache2ctl -S 2>&1 | perl -ne 'm@.*port\s+([0-9]+)\s+\w+\s+(\S+)\s+\((.+):.*@ && do { print "$2:$1\n\t$3\n"; $root = qx{grep DocumentRoot $3}; $root =~ s/^\s+//; print "\t$root\n" };'

lingo · 2009-07-21 10:51:30 3
disk space email alert

put it in crontab to get an alert when / is over 89% utilization.
This is sample output - yours may be different.
4

[ $(df / | perl -nle '/([0-9]+)%/ && print $1') -gt 90 ] && df -hP | mutt -s "Disk Space Alert -- $(hostname)" admin@example.com

grokskookum · 2009-10-15 21:11:54 8
Prints per-line contribution per author for a GIT repository

Figures out total line contribution per author for an entire GIT repo. Includes binary files, which kind of mess up the true count. If crashes or takes too long, mess with the ls-file option at the start: git ls-files -x "*pdf" -x "*psd" -x "*tif" to remove really random binary files git ls-files "*.py" "*.html" "*.css" to only include specific file types Based off my original SVN version: http://www.commandlinefu.com/commands/view/2787/prints-total-line-count-contribution-per-user-for-an-svn-repository Show Sample Output
This is sample output - yours may be different.
```
 217167 askedrelic
  11592 bob
   3975 alice
   1276 jim
    358 tom
     64 brad
     13 Not Committed Yet
```
4

git ls-files | xargs -n1 -d'\n' -i git-blame {} | perl -n -e '/\s\((.*?)\s[0-9]{4}/ && print "$1\n"' | sort -f | uniq -c -w3 | sort -r

askedrelic · 2009-10-25 01:44:03 11
Print a row of 50 hyphens

Perl is installed by default on most modern OS when jot is not. Show Sample Output
This is sample output - yours may be different.
```
--------------------------------------------------
```
4

perl -le'print"-"x50'

sputnick · 2010-01-06 17:06:07 4
most used commands in history (comprehensive)

Most of the "most used commands" approaches does not consider pipes and other complexities. This approach considers pipes, process substitution by backticks or $() and multiple commands separated by ; Perl regular expression breaks up each line using | or < ( or ; or ` or $( and picks the first word (excluding "do" in case of for loops) note: if you are using lots of perl one-liners, the perl commands will be counted as well in this approach, since semicolon is used as a separator Show Sample Output
This is sample output - yours may be different.
```
$ cat test
1  command file | command file | command | command
2  command <(command file) <(command file)
3  command file > file
4  for i in `command file`; do command file; command file; done | command
5  for i in $(command file); do command file; command file | command; done

$ cat test | perl -F"\||<\(|;|\`|\\$\(" -alne 'foreach (@F) { print $1 if /\b((?!do)[a-z]+)\b/i }' | sort | uniq -c | sort -nr | head

     16 command
      2 for
```
4

history | perl -F"\||<\(|;|\`|\\$\(" -alne 'foreach (@F) { print $1 if /\b((?!do)[a-z]+)\b/i }' | sort | uniq -c | sort -nr | head

alperyilmaz · 2010-04-08 13:46:09 4
convert ascii string to hex

just a bit simpler
This is sample output - yours may be different.
4

echo $ascii | perl -ne 'printf "%x", ord for split //'

linuxrawkstar · 2010-04-19 11:57:08 4
uniq without pre-sorting

Reads stdin, and outputs each line only once - without sorting ahead of time. This does use more memory than your system's sort utility.
This is sample output - yours may be different.
4

perl -ne 'print if !$a{$_}++'

doherty · 2011-02-17 02:18:44 7
Translate your terminal into Swedish Chef

Bork, bork, bork! To keep it short, the first terminal line doesn't show a prompt. Show Sample Output
This is sample output - yours may be different.
```
bork@bork:$ ps
  bork bork          bork bork
10640 bork/0    00:00:03 bork
12467 bork/0    00:00:00 bork
12469 bork/0    00:00:00 bork
12470 bork/0    00:00:00 bork
bork@bork:$ pwd 
/bork/bork/bork
bork@bork:$ whoami
bork
bork@bork:$
```
3

perl -e '$b="bork"; while(<STDIN>){$l=`$_ 2>&1`; $l=~s/[A-Za-z]+/$b/g; print "$l$b\@$b:\$ ";}'

fonik · 2009-02-05 18:33:40 28
How to pull out lines between two patterns

This command will display all lines between 2 patterns: word-a and word-b useful for grepping command outputs from file
This is sample output - yours may be different.
3

perl -0777 -ne 'print "$1\n" while /word-a(.*?)word-b/gs' filename.txt

eleffie · 2009-03-08 11:47:18 7
find the longest command in your history
This is sample output - yours may be different.
3

history | perl -lane '$lsize{$_} = scalar(@F); if($longest<$lsize{$_}) { $longest = $lsize{$_}; print "$_"; };' | tail -n1

salparadise · 2009-03-19 02:52:30 6
Do quick arithmetic on numbers from STDIN with any formatting using a perl one liner.

Good for summing the numbers embedded in text - a food journal entry for example with calories listed per food where you want the total calories. Use this to monitor and keep a total on anything that ouputs numbers. Show Sample Output
This is sample output - yours may be different.
```
echo "I had 10 goats, then sam brought 5 more. \
Then we bought 4 more goats and 2 goats had babies. \
How many goats did we have?" | \
perl -ne '$sum += $_ for grep { /\d+/ } split /[^\d\-\.]+/; print "$sum\n"'
21

perl -ne '$sum += $_ for grep { /\d+/ } split /[^\d\-\.]+/; print "$sum\n"'
1, '2' | 3, (-2) -.5
3.5
```
3

perl -ne '$sum += $_ for grep { /\d+/ } split /[^\d\-\.]+/; print "$sum\n"'

obscurite · 2009-06-16 06:39:08 6
Do a search-and-replace in a file after making a backup
This is sample output - yours may be different.
3

perl -i'.bak' -pe 's/old/new/g' <filename>

unixmonkey5248 · 2009-08-25 17:37:59 4
Find and display most recent files using find and perl

This pipeline will find, sort and display all files based on mtime. This could be done with find | xargs, but the find | xargs pipeline will not produce correct results if the results of find are greater than xargs command line buffer. If the xargs buffer fills, xargs processes the find results in more than one batch which is not compatible with sorting. Note the "-print0" on find and "-0" switch for perl. This is the equivalent of using xargs. Don't you love perl? Note that this pipeline can be easily modified to any data produced by perl's stat operator. eg, you could sort on size, hard links, creation time, etc. Look at stat and just change the '9' to what you want. Changing the '9' to a '7' for example will sort by file size. A '3' sorts by number of links.... Use head and tail at the end of the pipeline to get oldest files or most recent. Use awk or perl -wnla for further processing. Since there is a tab between the two fields, it is very easy to process. Show Sample Output
This is sample output - yours may be different.
```
find $HOME -type f -print0 | perl -0 -wn -e '@f=<>; foreach $file (@f){ (@el)=(stat($file)); push @el, $file; push @files,[ @el ];} @o=sort{$a->[9]<=>$b->[9]} @files; for $i (0..$#o){print scalar localtime($o[$i][9]), "\t$o[$i][-1]\n";}'|tail
Mon Sep 21 19:24:47 2009	/Users/andrew/Library/Logs/Sync/mobilemesyncstats.plist
Mon Sep 21 19:24:47 2009	/Users/andrew/Library/Preferences/ByHost/com.apple.DotMacSync.0019e366823e.plist
Mon Sep 21 19:24:48 2009	/Users/andrew/Library/Preferences/ByHost/com.apple.AOSNotification.0019e366823e.plist
Mon Sep 21 19:24:54 2009	/Users/andrew/Library/Cookies/Cookies.plist
Mon Sep 21 19:25:03 2009	/Users/andrew/Library/Preferences/com.apple.Terminal.plist
Mon Sep 21 19:26:44 2009	/Users/andrew/Library/Mail/IMAP-andrew@x-fifteen.com@mail.x-fifteen.com/Sent Messages.imapmbox/Messages/311191.emlx
Mon Sep 21 19:26:47 2009	/Users/andrew/Library/Logs/Sync/syncservices.log
Mon Sep 21 19:26:55 2009	/Users/andrew/Library/Preferences/com.apple.mail.plist
Mon Sep 21 19:27:48 2009	/Users/andrew/Library/Mail/IMAP-andrew@x-fifteen.com@mail.x-fifteen.com/INBOX.imapmbox/Messages/311201.emlx
Mon Sep 21 19:27:49 2009	/Users/andrew/Library/Mail/Envelope Index
```
3

find $HOME -type f -print0 | perl -0 -wn -e '@f=<>; foreach $file (@f){ (@el)=(stat($file)); push @el, $file; push @files,[ @el ];} @o=sort{$a->[9]<=>$b->[9]} @files; for $i (0..$#o){print scalar localtime($o[$i][9]), "\t$o[$i][-1]\n";}'|tail

drewk · 2009-09-21 22:11:16 11
clean up syntax and de-obfuscate perl script

the command show can be run in vim, here is the same thing on the command line cat script.pl | perl -MO=Deparse | perltidy
This is sample output - yours may be different.
3

%! perl -MO=Deparse | perltidy

grokskookum · 2009-09-24 03:32:04 8
Perl one liner for epoch time conversion

Converts Unix epoch time to localtime. Useful for any logs that only display epoch time. Show Sample Output
This is sample output - yours may be different.
```
perl -pe's/([\d.]+)/localtime $1/e;' /var/nagios/nagios.log

[Tue Jan 19 09:48:00 2010] HOST EVENT HANDLER: winboxen.example.com;(null);(null);(null);notify-host-by-email
```
3

perl -pe's/([\d.]+)/localtime $1/e;'

tuxtutorials · 2010-01-19 18:47:58 3
Convert files from DOS line endings to UNIX line endings

This method will also convert mac line endings.
This is sample output - yours may be different.
3

perl -pi -e 's/\r\n?/\n/g'

putnamhill · 2010-03-18 17:48:16 6
Print a list of installed Perl modules

This version works on an AIX system on which I have very limited permissions. The other version fails with "Can't open file /usr/opt/perl588/lib/site_perl/5.8.8/aix/auto/DBI/.packlist".
This is sample output - yours may be different.
3

perl -MFile::Find=find -MFile::Spec::Functions -Tlwe 'find { wanted => sub { print canonpath $_ if /\.pm\z/ }, no_chdir => 1 }, @INC'

randy909 · 2010-08-02 15:18:51 3

Join lines

This command turns a multi-line file into a single line joined with <SOMETEXT>. To skip blank lines, use: perl -pe '(eof()||s/^\s*$//)||s/\n/<SOMETEXT>/g' file.txt Show Sample Output

perl -pe 'eof()||s/\n/<SOMETEXT>/g' file.txt

eightmillion · 2010-12-02 01:19:27 5

Remove duplicate rows of an un-sorted file based on a single column

F[0] filters using first word. $F[1] - 2nd, and so on.
This is sample output - yours may be different.
3

perl -ane 'print unless $x{$F[0]}++' infile > outfile

depesz · 2010-12-15 17:46:22 3
read squid logs with human-readable timestamp

Show Sample Output
This is sample output - yours may be different.
```
before:
1310045550.240 0 10.10.10.27 TCP_HIT/200 1344 GET http://somedomain.com/ (...)
after:
[Thu Jul  7 15:32:30 2011].240 0 10.10.10.27 TCP_HIT/200 1344 GET http://somedomain.com (...)
```
3

tail -f /var/log/squid/access.log | perl -p -e 's/^([0-9]*)/"[".localtime($1)."]"/e'

godzillante · 2011-07-06 08:55:27 7
Use Perl like grep

If you've ever tried "grep -P" you know how terrible it is. Even the man page describes it as "highly experimental". This function will let you 'grep' pipes and files using Perl syntax for regular expressions. The first argument is the pattern, e.g. '/foo/'. The second argument is a filename (optional). Show Sample Output
This is sample output - yours may be different.
```
% printf "some\nfake\ntext\n" | prep '/^\s?[Ff]ake\s?$/'
fake
 
% printf "some\nfake\ntext\n" > file.txt

% prep '/^\s?[Ff]ake\s?$/' file.txt
fake
```
3

prep () { perl -nle 'print if '"$1"';' $2 }

dbbolton · 2011-08-13 14:29:26 6
sort lines by length

making it "sound" more "natural" language like -- additionally sorting the longest words alphabetically: this approach is using: * to get at all lines of input * post-"for" structure * short-circuit-or in sort: if the lengths are the same, then sort alphabetically otherwise don't even evaluate the right hand side of the or * -C sets all input and ouput channels to utf8
This is sample output - yours may be different.
3

perl -C -e 'print for sort { length $a <=> length $b or $a cmp $b } <>' < /usr/share/dict/words | tail

dbr · 2011-10-20 01:43:25 6
Print environment information.

Print environment (system) information using Perl.
This is sample output - yours may be different.
3

perl -e 'print map { $_ .= "$ENV{$_}\n" } (keys %ENV)'

MarxBro · 2012-10-13 23:38:28 6
FizzBuzz in Perl

Just another FizzBuzz in Perl. Show Sample Output
This is sample output - yours may be different.
```
1
2
Fizz
4
Buzz
Fizz
7
8
Fizz
Buzz
11
Fizz
13
14
Fizzbuzz
```
3

perl -E 'say$_%15?$_%3?$_%5?$_:Buzz:Fizz:Fizzbuzz for 1..100'

MarxBro · 2012-11-18 05:47:29 32
Show all available colors on your terminal.

Using perl and tput, show all the colors with numbers that your actual $TERM can handle. If want to remove the numbers at beginning of new line, it should be something like this: perl -E 'say `tput setb $_`," "x `tput cols`, `tput sgr0` for 0 .. (`tput colors` - 1)'
This is sample output - yours may be different.
3

perl -E 'say $_,`tput setb $_`," "x(`tput cols`-length("$_")),`tput sgr0` for 0..(`tput colors`-1)'

MarxBro · 2012-11-22 01:55:51 6
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Short and elegant way to backup a single file before you change it.

Remember to backup everything before changing it so you can restore all to normal.

Redirect incoming traffic to SSH, from a port of your choosing

Stuck behind a restrictive firewall at work, but really jonesing to putty home to your linux box for some colossal cave? Goodness knows I was...but the firewall at work blocked all outbound connections except for ports 80 and 443. (Those were wide open for outbound connections.) So now I putty over port 443 and have my linux box redirect it to port 22 (the SSH port) before it routes it internally. So, my specific command would be: $iptables -t nat -A PREROUTING -p tcp --dport 443 -j REDIRECT --to-ports 22 Note that I use -A to append this command to the end of the chain. You could replace that with -I to insert it at the beginning (or at a specific rulenum). My linux box is running slackware, with a kernel from circa 2001. Hopefully the mechanics of iptables haven't changed since then. The command is untested under any other distros or less outdated kernels. Of course, the command should be easy enough to adapt to whatever service on your linux box you're trying to reach by changing the numbers (and possibly changing tcp to udp, or whatever). Between putty and psftp, however, I'm good to go for hours of time-killing.

Export a subset of a database

Limits the number of rows per table to X

Open multiple tabs in Firefox from a file containing urls

this will open a new tab in firefox for every line in a file the sleep is removable but i found that if you have a large list of urls 50+, and no sleep, it will try to open all the urls at once and this will cause them all to load a lot slower, also depending on the ram of your system sleep gives you a chance to close the tabs before they overload your ram, removing & >2/dev/null will yield unpredictable results.

SSH Auto-login with password

You need to install "sshpass" for this to work. apt-get install sshpass

Get AWS temporary credentials ready to export based on a MFA virtual appliance

You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Play radio stream with mplayer

Above command will play Virgin Radio Dubai

Output system statistics every 5 seconds with timestamp

See man vmstat for information about the statistics. This does the same thing without the timestamp: $vmstat 5

Find usb device in realtime

Using this command you can track a moment when usb device was attached.

Get AWS temporary credentials ready to export based on a MFA virtual appliance

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Commands using perl (369)

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