! time_test.f90

program time_test
  implicit none
  double precision :: start, now, next
  integer :: clock_count, clock_rate, clock_max
  integer :: i=0

  print *, 'time_test'
  call system_clock(count=clock_count, count_rate=clock_rate, &
                    count_max=clock_max)
  print *, 'clock_count=', clock_count, ', clock_rate=', clock_rate, &
           ', clock_max=', clock_max
  start = (1.0D0+clock_count)/clock_rate

  print *, i, ' should print every 5 seconds'
  call system_clock(count=clock_count)
  now = (1.0D0+clock_count)/clock_rate
  do while(i<90)
    call system_clock(count=clock_count)
    next = (1.0D0+clock_count)/clock_rate
    if(next>now+5.0) then
      i = i+5
      print *, i
      now = next
    end if
  end do
  print *, ' took ', now-start, ' seconds'

end program time_test