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

my $flag;
while (<DATA>) {
   if (/\/\*/) {
      $flag=!$flag; #turns on and off
      next;
   }
   if ( ($flag) && /\/{2,2}(.*)/) {
      print "$1\n";
   }
}

__DATA__
// useless comment

Some Code

//**********************************************************
//
//I need that text
//   And that also
//
//**********************************************************

Some Code

// useless comment
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