module M_time contains subroutine system_sleep(wait) use,intrinsic :: iso_c_binding, only: c_int integer,intent(in) :: wait integer(kind=c_int):: waited interface function c_usleep(msecs) bind (C,name="usleep") import integer(c_int) :: c_usleep integer(c_int),intent(in),VALUE :: msecs end function c_usleep end interface if(wait.gt.0)then waited=c_usleep(int(wait,kind=c_int)) endif end subroutine system_sleep end module M_time program x use M_time call system_sleep(5000000) end