Don't use regular expressions to parse HTML. Use a proper parser: 
#!/usr/bin/perl
use warnings;
use strict;

use XML::LibXML;

my $html = 'XML::LibXML'->load_html( string => << '__HTML__');
<form method="post" action="logout.lp" name="authform" id="logoutform"
+>
        <input type="hidden" name="rn" value="-1383135969">
<form method="post" action="login.lp" name="authform" id="authform">
        <input type="hidden" name="rn" value="-1383135969">
__HTML__

my $value = $html->findvalue('//form[@action="login.lp"]/input[@name="
+rn"]/@value');
print $value, "\n";

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لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ

In reply to Re: regex match after pattern by choroba
in thread regex match after pattern by littleperl

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