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

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

my @start = gettimeofday ();
my $sleep = nanosleep(1000);
my @end = gettimeofday ();
print "[$sleep][@start][@end]\n";

Results:
[1000][1345190945 846575][1345190945 846739]

##</code><code>##

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

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

my @start = gettimeofday ();
my @end = gettimeofday ();
print "[@start][@end]\n";

Results:
[1345190988 610721][1345190988 610723]