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

use Time::HiRes qw(usleep nanosleep gettimeofday);

my @start = gettimeofday ();
my $sleep = usleep(1);
my @end = gettimeofday ();
print "[$sleep][@start][@end]\n";

---------------------------------------
Sample Results:
[805][1345188496 560216][1345188496 561029]