#!/usr/local/bin/perl

use strict;
use warnings;

open my $fh, '<', 'binary.file' or die "File not found: $!";

binmode($fh);

my ($xdr, $buffer, $length) = "";

# read until end of file ...
while (read ($fh, $buffer, 2) != 0) {   

# if file does not start with eye catcher skip until you find one
    next unless ((unpack 'H*', $buffer) eq "3d3d");  

 # append the eyecatcher to xdr variable
    $xdr .= $buffer;   

# read next two bytes which is length of the record
    read ($fh, $buffer, 2); 

# convert the binary length to decimal for use in read function
    my $length = unpack('s',pack 's', hex(unpack 'H*', $buffer)); 

# append the length to xdr variable
    $xdr .= $buffer; 

# read the binary stream till the length of record - 4 bytes 
    read ($fh, $buffer, $length-4); 

 # append the entire xdr
    $xdr .= $buffer;

    #send to parsing subroutine for parsing

    $xdr = "";
}