#!/usr/bin/perl
# Create 1 GB file if you do not have one:
# dd if=/dev/urandom of=test.bin bs=1048576 count=1000
use strict; use warnings;
use Sys::Mmap;
open (my $fh, "test.bin") or die "open: $!";
my $t = time;
print "mmapping.. ";
mmap (my $mh, 0, PROT_READ, MAP_SHARED, $fh) or die "mmap: $!";
my @all_b = $mh =~ /0xb/g;
my $cnt = @all_b;
my $runtime = time()-$t;
print STDERR "found $cnt 0xb, in $runtime  seconds\n";