#! perl
use strict;
use warnings;

use constant
{
    DELAY  =>   10,
    EXPIRY => 3600,
    MARGIN =>  300,
};

my $time   =  time;
my $expiry = $time + EXPIRY;

while ($time + MARGIN < $expiry)
{
    my $previoustime = $time;
    warn $time;

    sleep DELAY + $previoustime - $time
        unless $time - $previoustime >= DELAY;

    $time = time;
}

##</code><code>##

16:17 >perl 1453_SoPW.pl
1447741073 at 1453_SoPW.pl line 18.
1447741083 at 1453_SoPW.pl line 18.
1447741093 at 1453_SoPW.pl line 18.
1447741103 at 1453_SoPW.pl line 18.
1447741113 at 1453_SoPW.pl line 18.
...

##</code><code>##

( $time - $previoustime >= 10
  or sleep (10 + $previoustime - $time)
)