use strict;
use warnings;

my $cmd = "/usr/sbin/ntpq -p";

my @ntpout = `$cmd`;
die "$cmd failed with: $^E, $?" unless(@ntpout);

my $current_time_source = (grep(/^\*/, @ntpout))[0];
die "Not synchronized" unless($current_time_source);

my $offset = (split(/\s+/, $current_time_source))[8];
die "$current_time_source: No offset" unless(defined($offset));

print "$offset\n";