Read a file and output it as a string that can be pasted as binar payload

file2payload.pl

#!/usr/bin/perl

# Reads a file one byte a time and prints it out prepended by "\x".
# Example:
# $ xxd a
# 00000000: ffe4                                     ..
# $ ./file2hexstring.pl a
# \xff\xe4

use strict;
use warnings;

my $file = $ARGV[0];

print("# Payload:\n\n");

my $payload_length = 0;
open my $fh, '<:raw', $file;
while(my $bytes_read = read $fh, my $bytes, 1) {
    printf("\\x%02x", ord($bytes));
    $payload_length++;
}
print("\n\n");

print("# Length: $payload_length bytes.\n");
close($file);