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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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Commands tagged perl from sorted by
Terminal - Commands tagged perl - 178 results
soxi -D * | awk '{SUM += $1} END { printf "%d:%d:%d\n",SUM/3600,SUM%3600/60,SUM%60}'
perl -ne [email protected]=split(/,/); $b=0; foreach $r (1..$#a){ $b+=$a[$r] } print "$a[0],$b\n"' -f file.csv
2015-09-04 21:05:56
User: miniker84
Functions: perl

For all lines, sum the columns following the first one, and then print the first column plus the sum of all the other columns.

example input:






perl -pE's/(\S+\s*){0,1}//'
2015-05-09 15:14:58
User: pung96
Functions: perl

An advantage is that this doesn't modify remained string at all. One can change {0,1} with {0,n} to drop several columns

echo FileName | perl -nlE'sleep 1 while time-(stat)[10]<10' && echo DONE
2015-05-09 14:58:41
User: pung96
Functions: echo perl

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

perl -e 'for(;;sleep 1){printf"\r"."%.4b "x6,split"",`date +%H%M%S`}'
mtr www.google.com
finger $(whoami) | perl -ne '/Name: ([a-zA-Z0-9 ]{1,})/ && print "$1\n"'
catmandu convert JSON --multiline 1 to YAML < file.json > file.yaml
2014-09-29 16:45:24
Tags: perl json yaml

This is based on __unixmonkey73469__ answer. You will need to supply `--multiline 1` option to JSON importer if your .json is multiline (i.e. it was prettyfied)

And you still need catmandu installed via `cpanm Catmandu`

perl -MPOSIX -le 'print strftime "%F", localtime 1234567890'
hl() { while read -r; do printf '%s\n' "$(perl -p -e 's/('"$1"')/\a\e[7m$1\e[0m/g' <<< "$REPLY")"; done; }
perl -M URI::Escape -lne 'print uri_unescape($_)'
/bin/echo -e '\002Hello, Folks\t!\r' | perl -pwle 'use v5.14; s/([\N{U+0000}-\N{U+0020}])/chr(9216+ord($1))/ge;'
2014-06-30 01:45:40
User: scruss
Functions: perl

Converts control codes and spaces (ASCII code ≤ 32) to visible Unicode Control Pictures, U+2400 ? U+2420. Skips \n characters, which is probably a good thing.

rename 's/result_([0-9]+)_([0-9]+)_([0-9]+)\.json\.txt/sprintf("%d%02d%02d.txt",$3,$2,$1)/ge' result_*.txt
2014-06-13 07:34:32
User: sucotronic
Functions: rename
Tags: perl rename

Given a bunch of files with "wrong" date naming, it renames them in a "good" format.

perl -ne 'if (/^(\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2},\d{3} )/ ) { $t=$1; print $_ } else { print $t . $_ }'
2014-05-21 08:54:27
Functions: perl

If you have a logfile where some lines start with timestamps like "2014-05-01 12:34:56,123" but other lines are missing the timestamp (like stack traces or object dumps), then use this script to copy the most recent timestamp to any lines that are missing it.

This is useful for merging log files, since you can then safely sort by timestamp to merge the files.

find . -name '*.phtml' | xargs perl -pi -e 's/(?!(<\?(php|xml|=)))<\?/<\?php/g;'
2014-05-07 14:33:19
User: crashspeeder
Functions: find perl xargs

Tired of front end developers using short open tags in your views? This will replace all instances of

perl -nle 'print length,"\t",$_ if length > 37' < /path/to/input/file
perldoc -m Some::Module
for i in $(find . -regex '.*\/C.*\.cpp'); do svn mv `perl -e 'my $s=$ARGV[0]; $s=~m/(.*\/)C(.*)/; print "$s $1$2"' "$i"`; done
du -g | perl -ne 'print if (tr#/#/# == <maximum depth>)'
2014-02-15 07:33:36
User: RAKK
Functions: du perl
Tags: perl du unix aix

Lists directory size up to a maximum traversal depth on systems like IBM AIX, where the du command doesn't have Linux's --max-depth option. AIX's du uses -g to display directory size on gigabytes, -m to use megabytes, and -k to use kilobytes. tr### is a Perl function that replaces characters and returns the amount of changed characters, so in this case it will return how many slashes there were in the full path name.

ls -1 | xargs ruby -e'puts ARGV.shuffle'
perl -Mojo -E 'say g("http://www.census.gov/popclock/data/population/world")->json->{'world'}{'population'};'
logger -tdnsupdate $(curl -s 'https://dynamicdns.park-your-domain.com/update?host=@&domain=xxx&password=xxx'|tee -a /root/dnsupdate|perl -pe'/Count>(\d+)<\/Err/;$_=$1eq"0"?"Update Sucessful":"Update failed"'&&date>>/root/dnsupdate)
2013-08-11 16:27:39
User: MagisterQuis
Functions: logger perl tee

Sets the @ A record for your domain hosted by namecheap to your current internet-facing IP address, logs success or failure with syslog, and logs the data returned to /root/dnsupdate.

Change the XXX's as appropriate.

More info at: http://www.namecheap.com/support/knowledgebase/article.aspx/29/

perl -le '$l=80;$l2="!" x $l;substr+($l2^=$l2),$l/2,1,"\xFF";{local $_=$l2;y/\0\xFF/ ^/;print;($lf,$rt)=map{substr $l2 x 2,$_%$l,$l;}1,-1;$l2=$lf^$rt;select undef,undef,undef,.1;redo}'
2013-06-21 06:00:24
User: l3v3l
Functions: perl

xmas lights for your terminal - switching the $l value to something like 1200 and zooming out on your terminal gives a great view ...

$text = do {local(@ARGV, $/) = $file ; <>; }; [or] sub read_file { local(@ARGV, $/) = @_ ; <>; }
2013-06-12 11:41:49
User: matya

Found it on:


The yet most simple way to read all the contents of a file to a variable. I used it in a perl script to replace $text="`cat /sys/...`", and stipping down 9 secs of runtime due less forks

pwd|grep -o '/'|perl -ne '$x.="./.";print`readlink -f $x`'|xargs -tn1 chmod 755
2013-03-14 12:03:44
Functions: chmod grep perl pwd xargs

`pwd` returns the current path

`grep -o` prints each slash on new line

perl generates the paths sequence: './.', './../.', ...

`readlink` canonicalizes paths (it makes the things more transparent)

`xargs -tn1` applies chmod for each of them. Each command applied is getting printed to STDERR.