On Mar 25, 2014, at 10:13 AM, Junchao Zhang <[email protected]> wrote:

How to get the length? Use len(argv(i)) and select an arbitrary i ?

len(argv) will do. If the argument of LEN is an array, the result is the length of one element of the array. Cheers, Bill

--Junchao Zhang

On Tue, Mar 25, 2014 at 9:59 AM, Bill Long <[email protected]> wrote:

On Mar 25, 2014, at 9:51 AM, Junchao Zhang <[email protected]> wrote:

...

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(*).

It is unreasonable. All elements of a character array have the same length.

Cheers, Bill

...

Thank you --Junchao Zhang _______________________________________________ mpiwg-fortran mailing list [email protected] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-fortran

Bill Long [email protected] Fortran Technical Suport & voice: 651-605-9024 Bioinformatics Software Development fax: 651-605-9142 Cray Inc./ Cray Plaza, Suite 210/ 380 Jackson St./ St. Paul, MN 55101

_______________________________________________ mpiwg-fortran mailing list [email protected] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-fortran

_______________________________________________ mpiwg-fortran mailing list [email protected] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpiwg-fortran

Bill Long [email protected] Fortran Technical Suport & voice: 651-605-9024 Bioinformatics Software Development fax: 651-605-9142 Cray Inc./ Cray Plaza, Suite 210/ 380 Jackson St./ St. Paul, MN 55101