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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Maintained by Jon H.

Site originally by David Winterbottom (user root).

Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Commands using perl from sorted by
Terminal - Commands using perl - 345 results
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;'
2009-09-24 23:37:36
User: drewk
Functions: perl sed
Tags: perl sed curl

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)

find -type f -name "*.avi" -print0 | xargs -0 mplayer -vo dummy -ao dummy -identify 2>/dev/null | perl -nle '/ID_LENGTH=([0-9\.]+)/ && ($t +=$1) && printf "%02d:%02d:%02d\n",$t/3600,$t/60%60,$t%60' | tail -n 1
2009-09-24 15:50:39
User: syssyphus
Functions: find perl printf tail xargs

change the *.avi to whatever you want to match, you can remove it altogether if you want to check all files.

cat ~/SortedFile.txt | perl -wnl -e '@f=<>; END{ foreach $i (reverse 0 .. $#f) { $r=int rand ($i+1); @f[$i, $r]=@f[$r,$i] unless ($i==$r); } chomp @f; foreach $line (@f){ print $line; }}'
2009-09-24 15:42:43
User: drewk
Functions: cat perl

The sort utility is well used, but sometimes you want a little chaos. This will randomize the lines of a text file.

BTW, on OS X there is no

| sort -R

option! There is also no

| shuf

These are only in the newer GNU core...

This is also faster than the alternate of:

| awk 'BEGIN { srand() } { print rand() "\t" $0 }' | sort -n | cut -f2-
%! perl -MO=Deparse | perltidy
2009-09-24 03:32:04
User: syssyphus
Functions: perl

the command show can be run in vim, here is the same thing on the command line

cat script.pl | perl -MO=Deparse | perltidy
perl -MCPAN -e 'CPAN::Shell->install(CPAN::Shell->r)'
perl -e "alarm 10; exec @ARGV" "somecommand"
2009-09-23 12:03:55
User: jgc
Functions: perl

In this example the command "somecommand" will be executed and sent a SIGALARM signal if it runs for more than 10 seconds. It uses the perl alarm function. It's not 100% accurate on timing, but close enough. I found this really useful when executing scripts and commands that I knew might hang E.g. ones that connect to services that might not be running. Importantly this can be used within a sequential script. The command will not release control until either the command completes or the timeout is hit.

perl -le 'print join $/, @INC'
2009-09-22 22:18:35
User: chuckr
Functions: join perl

This will show where your Perl installation is looking for modules.

perl -le 'use Config; foreach $i (keys %Config) {print "$i : @Config{$i}"}'
2009-09-22 22:14:21
User: chuckr
Functions: perl
Tags: perl

This dumps all of your installed perl's config information.

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
2009-09-21 22:11:16
User: drewk
Functions: find 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.

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
2009-09-17 16:14:52
User: salparadise
Functions: perl

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"

it will only print the "" portion

perl -i -pe 's/\xef\xbb\xbf//g' <file>
perl -e "print scalar(gmtime(1247848584))"
2009-09-11 06:19:09
User: opexxx
Functions: perl
Tags: perl

print scalar gmtime

perl -lne '$l{$_}=length;END{for(sort{$l{$a}<=>$l{$b}}keys %l){print}}' < /usr/share/dict/words | tail
curl -u username --silent "https://mail.google.com/mail/feed/atom" | perl -ne 'print "\t" if /<name>/; print "$2\n" if /<(title|name)>(.*)<\/\1>/;
2009-09-09 23:25:05
User: suxer
Functions: perl

notice what happens when there is more than one unread message in a thread...

also people please dont hardcode the password when you use curl. Leave it out and curl will ask you when it runs. Please...?

system_profiler SPApplicationsDataType | perl -nl -e '@al=<>; $c=@al; while($j<$c){ $apps[$i].=$al[$j]; $i++ if ($al[$j] ) =~ /^\s\s\s\s\S.*:$/; $j++} while($k<$i){ $_=$apps[$k++]; if (/Kind: PowerPC/s) {print;}}'
2009-09-06 20:56:48
User: drewk
Functions: perl
Tags: Os X perl

This finds all the PowerPC apps recognized by OS X.

A better version is:

system_profiler SPApplicationsDataType 2> /dev/null | perl -

wnl -e '$i=$j=$k=$p=0; @al=; $c=@al; while($j

s[$i].=$al[$j]; $i++ if ($al[$j]) =~ /^\s\s\s\s\S.*:$/; $j++} while($k

apps[$k++]; if (/Kind: PowerPC/s) {print; $p++;}} print "$i applications, $p P

owerPC applications\n\n"'

but that is more than 255 characters...

lspci -v | perl -ne '/VGA/../^$/ and /VGA|Kern/ and print'
for x in `seq 0 25 $(curl "http://www.commandlinefu.com/commands/browse"|grep "Terminal - All commands" |perl -pe 's/.+(\d+),(\d+).+/$1$2/'|head -n1)`; do curl "http://www.commandlinefu.com/commands/browse/sort-by-votes/plaintext/$x" ; done > a.txt
2009-08-27 11:02:53
User: SuperFly
Functions: grep head perl

'jot' does not come with most *nix distros, so we need to use seq to make it work. This version tested good on Fedora 11.

for x in `jot - 0 \`curl "http://www.commandlinefu.com/commands/browse"|grep "Terminal - All commands" |perl -pe 's/.+(\d+),(\d+).+/$1$2/'|head -n1\` 25`; do curl "http://www.commandlinefu.com/commands/browse/sort-by-votes/plaintext/$x" ; done >a.txt
2009-08-25 21:57:15
Functions: grep head perl

This is an extension of a previous command by satyavvd on 2009-07-23 12:04:02, but this one grabs the whole archive. Hard coded numbers in previous script capped number of commands that could be fetched. This one grabs them all regardless of how big the archive gets.

perl -i'.bak' -pe 's/old/new/g' <filename>
perl -e 'print scalar(gmtime(1234567890)), "\n"'
find /var/www/ -type f -name ".htaccess" -exec perl -pi -e 's/AddHandler[\s]*php(4|5)-cgi/AddHandler x-httpd-php\1/' {} \;
2009-08-21 21:55:22
User: foob4r
Functions: find perl

Alter "AddHandler php5-cgi .php" and "AddHandler php4-cgi .php" entries to new "AddHandler x-httpd-php5 .php" respective php4 entries in all .htaccess files under /var/www

git diff --numstat -w --no-abbrev | perl -a -ne '$F[0] != 0 && $F[1] !=0 && print $F[2] . "\n";'
2009-08-19 05:07:58
User: lingo
Functions: diff perl

Only shows files with actual changes to text (excluding whitespace). Useful if you've messed up permissions or transferred in files from windows or something like that, so that you can get a list of changed files, and clean up the rest.

perl -F' ' -MDate::Format -pale 'substr($_, index($_, $F[1]), length($F[1]), time2str("%C", $F[1]))' file.log
2009-08-13 13:57:33
Functions: perl
Tags: perl log

When you have one of those (log)files that only has epoch for time (since no one will ever look at them as a date) this is a way to get the human readable date/time and do further inspection.

Mostly perl-fu :-/

perl -F',' -ane '$a += $F[3]; END { print $a }' test.csv
2009-08-11 15:08:58
Functions: perl
Tags: awk column CSV sum

More of the same but with more elaborate perl-fu :-)

perl -p -i -e 's/this/that/g' filename