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Commands tagged perl from sorted by
Terminal - Commands tagged perl - 164 results
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
0

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
1

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
0

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
0

Found it on:

http://stackoverflow.com/questions/318789/whats-the-best-way-to-open-and-read-a-file-in-perl

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
0

`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.

FULLPATH=$(perl -e "use Cwd 'abs_path';print abs_path('$0');")
2013-02-01 20:09:34
User: follier
Functions: perl
0

Since none of the systems I work on have readlink, this works cross-platform (everywhere has perl, right?).

Note: This will resolve links.

perl -MModule::Name\ 9999 -e 1
2013-01-15 22:51:39
User: three18ti
Functions: perl
Tags: bash perl zsh
-1

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.

perldoc -l Module::Name 2>/dev/null
2013-01-11 23:28:13
User: MarxBro
Tags: bash perl
4

Shows the path if the module is installed or exit quietly (to simply avoid the 'No documentation found' msg).

module_exists(){ perl -e 'use '$1 2>/dev/null; }
2013-01-11 14:47:07
User: putnamhill
Functions: perl
Tags: bash perl
-2

This version uses a bash function and does not print the path to the module.

perl -E 'say $_,`tput setb $_`," "x(`tput cols`-length("$_")),`tput sgr0` for 0..(`tput colors`-1)'
2012-11-22 01:55:51
User: MarxBro
Functions: perl
Tags: perl color tput
3

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 $_`," "x `tput cols`, `tput sgr0` for 0 .. (`tput colors` - 1)'
perl -E 'say$_%15?$_%3?$_%5?$_:Buzz:Fizz:Fizzbuzz for 1..100'
2012-11-18 05:47:29
User: MarxBro
Functions: perl
Tags: perl fizzbuzz
3

Just another FizzBuzz in Perl.

perl -e 'print "$_=$ENV{$_}\n" for keys %ENV'
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)}'
perl -e 'print map { $_ .= "$ENV{$_}\n" } (keys %ENV)'
2012-10-13 23:38:28
User: MarxBro
Functions: perl
3

Print environment (system) information using Perl.

brd = "! f() { for k in $(git branch $@ | sed 's/^..//; s/ .*//'); do echo "$(git log -1 --pretty='%Cgreen%ci %Cblue(%cr)%Creset ' $k) $k" ; done | sort -r; }; f"
2012-09-28 10:20:51
0

Add this line to your ~/.gitconfig for a git alias "git brd" (i.e., brd = (br)anch+(d)ate) which sorts branches by date. Allows you to pass in limited "git branch" options such as "-r" (remote) or "-a" (all). (Note: forum added "$" prefix to command; obviously in gitconfig there is no "$" prefix.)

ping g.co|perl -ne'$|=/e=(\S+)/||next;(push@_,$1)>30&&shift@_;print"\r",(map{"\xe2\x96".chr(128+7*$_/(sort{$b<=>$a}@_)[0])." "}@_),"$1ms"'
2012-07-06 22:42:06
User: bartgrantham
Functions: perl ping
0

Nasty perl one-liner that provides a sparkline of ping times. If you want a different history than the last 30, just put that value in. It (ab)uses unicode to draw the bars, inspired by https://github.com/joemiller/spark-ping . It's not the most bug-free piece of code, but what it lacks in robustness it makes up for in capability. :)

If anyone has any ideas on how to make it more compact or better, I'd love to hear them.

I included a ping to google in the command just as an example (and burned up 10 chars doing it!). You should use it with: $ ping example.com | $SPARKLINE_PING_COMMAND

perl -e 'printf "00:16:3E:%02X:%02X:%02X\n", rand 0xFF, rand 0xFF, rand 0xFF'
for f in `find . -name "*.php"`; do perl -p -i.bak -e 's/<\?php \/\*\*\/ eval\(base64_decode\(\"[^\"]+"\)\);\?>//' $f; done
2012-03-12 10:44:33
User: lizuka
Functions: perl
0

loop through files in .php extension

make a .bak of each of them

find the base64_decode function and remove it

curl -s -d "CSField=Name" -d "CSInput=BostonUCompSci" http://torstatus.blutmagie.de/index.php | grep -oP "ip=\K(\d+)(\.\d+){3}"
2012-03-09 16:52:27
User: JisSey
Functions: grep
0

Reciprocally, we could get the node name from a give Tor IP address =>

ip2node() { curl -s -d "QueryIP=$1" http://torstatus.blutmagie.de/tor_exit_query.php | grep -oP "Server name:.*'>\K\w+" ; }

ip2node 204.8.156.142

BostonUCompSci

perl -e "print 'yes' if `exim -bt $s_email_here | grep -c malformed`;"
2012-02-28 04:42:41
User: DewiMorgan
Functions: perl
0

People are *going* to post the wrong ways to do this. It's one of the most common form-validation tasks, and also one of the most commonly messed up. Using a third party tool or library like exim means that you are future-proofing yourself against changes to the email standard, and protecting yourself against the fact that actually checking whether an email address is valid is *not possible*.

Still, perhaps your boss is insisting you really do need to check them internally. OK.

Read the RFCs. The bet before the @ is specified by RFC2821 and RFC2822. The domain name part is specified by RFC1035, RFC1101, RFC1123 and RFC2181.

Generally, when people say "email address", they mean that part of the address that the RFC terms the "addr-spec": the "blah@domain.tld" address, with no display names, comments, quotes, etc. Also "root@localhost" and "root" should be invalid, as should arbitrary addressing schemes specified by a protocol indicator, like "jimbo@myprotocol:foo^bar^baz".

So... With the smallest poetic license for readability (allowing underscores in domain names so we can use "\w" instead of "[a-z0-9]"), the RFCs give us:

^(?:"(?:[^"\\]|\\.)+"|[-^!#\$%&'*+\/=?`{|}~.\w]+)@(?=.{3,255}$)(?:[\w][\w-]{0,62}\.){1,128}[\w][\w-]{0,62}$

Not perfect, but the best I can come up with, and most compliant I've found. I'd be interested to see other people's ideas, though. It's still not going to verify you an address fersure, properly, 100% guaranteed legit, though. What else can you do? Well, you could also:

* verify that the address is either a correct dotted-decimal IP, or contains letters.

* remove reserved domains (.localhost, .example, .test, .invalid), reserved IP ranges, and so forth from the address.

* check for banned domains (whitehouse.gov, example.com...)

* check for known TLDs including alt tlds.

* see if the domain has an MX record set up: if so, connect to that host, else connect to the domain.

* see if the given address is accepted by the server as a recipient or sender (this fails for yahoo.*, which blocks after a few attempts, assuming you are a spammer, and for other domains like rediffmail.com, home.com).

But these are moving well out of the realm of generic regex checks and into the realm of application-specific stuff that should be done in code instead - especially the latter two. Hopefully, this is all you needed to point out to your boss "hey, email validation this is a dark pit with no bottom, we really just want to do a basic check, then send them an email with a link in it: it's the industry standard solution."

Of course, if you want to go nuts, here's an idea that you could do. Wouldn't like to do it myself, though: I'd rather just trust them until their mail bounces too many times. But if you want it, this (untested) code checks to see if the mail domain works. It's based on a script by John Coggeshall and Jesse Houwing that also asked the server if the specific email address existed, but I disliked that idea for several reasons. I suspect: it will get you blocked as a spambot address harvester pretty quick; a lot of servers would lie to you; it would take too much time; this way you can cache domains marked as "OK"; and I suspect it would add little to the reliability test.

// Based on work by: John Coggeshall and Jesse Houwing.

// http://www.zend.com/zend/spotlight/ev12apr.php

mailRegex = '^(?:"(?:[^"\\\\]|\\\\.)+"|[-^!#\$%&\'*+\/=?`{|}~.\w]+)';

mailRegex .= '@(?=.{3,255}$)(?:[\w][\w-]{0,62}\.){1,128}[\w][\w-]{0,62}$';

function ValidateMail($address) {

  global $mailRegex; // Yes, globals are evil. Put it inline if you want.

  if (!preg_match($mailRegex)) {

    return false;

  }

  list ( $localPart, $Domain ) = split ("@",$Email);

  // connect to the first available MX record, or to domain if no MX record.

  $ConnectAddress = new Array();

  if (getmxrr($Domain, $MXHost)) {

    $ConnectAddress = $MXHost;

  } else {

    $ConnectAddress[0] = $Domain;

  }

  // check all MX records in case main server is down - may take time!

  for ($i=0; $i < count($ConnectAddress); $i++ ) {

    $Connect = fsockopen ( $ConnectAddress[$i], 25 );

    if ($Connect){

      break;

    }

  }

  if ($Connect) {

    socket_set_blocking($Connect,0);

    // Only works if socket_blocking is off.

    if (ereg("^220", $Out = fgets($Connect, 1024))) {

      fclose($Connect); // Unneeded, but let's help the gc.

      return true;

    }

    fclose($Connect); // Help the gc.

  }

  return false;

}