! g77 -c f77sub.f ! F f77sub.o f_calls_f77.f95 ! ./a.out ! The value of arg is 42 program f_calls_f77 integer, parameter :: n = 42 call f77sub (n) end program f_calls_f77 ! file f77sub.f: ! subroutine f77sub(arg) ! ! print *, "The value of arg is ", arg ! ! end