\@ should work. Are you sure $line contains what you think it does? Perhaps if you gave us a little more code? 

#!/usr/bin/perl
use strict;
use warnings;

my $line = 'sometext@@sometext';
if ($line =~ m|\@\@|) {
    print "success!\n";
}

[download]

I'm willing to bet that what is going on is described in Quote and Quote like Operators.

In reply to Re: regular expression with @@/ by kennethk
in thread regular expression with @@/ by jim_neophyte

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