#! /usr/bin/perl -w

die "perl5 needed\n" unless ($] > 5);

use Getopt::Std;

$opt_f = 0;			# 'Hard' failure if 'state' is unknown
$opt_n = 1000;			# How many tries before we give up? (10 min+)
$opt_s = 6;			# Seconds to sleep between tries (6s = 10/min)
$opt_v = 0;			# Be verbose?

getopts('fn:s:v');

$cmd = 'ntpq -c "rv 0 state"';

$| = 1;				# Autoflush output.

print "Waiting for ntpd to synchronize...  " if ($opt_v);
for ($i = 0; $i < $opt_n; ++$i) {
    open(Q, $cmd." 2>&1 |") || die "Can't start ntpq: $!";
    while(<Q>) {
      if (/^state=4/) {
	print "\bOK!\n" if ($opt_v);
	exit 0;
      }

      if (/request variable was unknown/) {
	print "\bCan't tell!\nPerhaps you are running an old version of ntpd.\n" if ($opt_v);
	exit $opt_f;
      }

      if (/Connection refused/) {
	print "\bntpd is not running!\n" if ($opt_v);
	exit 1;
      }
    }
    close(Q);
    print "\b".substr("*+:.", $i % 4, 1) if ($opt_v);
    sleep($opt_s);
}
print "\bNo!\nntpd did not synchronize.\n" if ($opt_v);
exit 1;