my ($quit, $next_print, $next_foo) = (0, 0, 0);
while (!$quit) {
   <<<do stuff>>>
   my $cur_time = time;
   if (time > $next_print) {
      print "...\n";
      $next_print = time+5;  # wait 5s for next print
   }
   if (time > $next_foo) {
      foo(...);
      $next_foo = time+7;    # wait 7s for next foo()
   }
   <<<do more stuff>>>
}