Hello, Fortran experts, p.377 of MPI3 defines prototype of MPI_Comm_spawn. MPI_Comm_spawn(command, argv, maxprocs, info, root, comm, intercomm, array_of_errcodes, ierror) CHARACTER(LEN=*), INTENT(IN) :: command, argv(*) ... I can understand that command is a variable-length character. I fetch its length by len(command). The Fortran compiler needs to pass in data of command, as well as length of command. But I can't understand argv(*). I interpret it as an assumed-size array of variable-length characters. Does that imply each argv(i) could have different lengths, e.g., len(argv(1)) may be different from len(argv(2))? I think it is unreasonable, since if that, the compiler has to pass in length of every element of argv(*). Thank you --Junchao Zhang