From: treumann@XXXXXXXXXX
X-Lotus-FromDomain: IBMUS
To: mpi-core@XXXXXXXXXXX
Date: Mon, 20 Dec 1999 11:10:56 -0500
Subject: MPI_GET_PROCESSOR_NAME & Fortran
Sender: owner-mpi-core@XXXXXXXXXXX

Both Nils Jonsson and Jim Cownie have suggested that MPI_GET_PROCESSOR_NAME
in Fortran ought to behave like Fortran character assignment by supplying
the right number of trailing blanks.  The problem is that Fortran character
assignment is done by the compiler. It "knows" how long a sting is in the
case of a local declaration. It "knows" where to look for the length hidden
parameter when a string is passed to a subroutine.

As Implementor of an MPI tied to a specific compiler (xlf for AIX), I also
"know" where to find the hidden parameter that gives a string's length and
could do as Nils and Jim suggest.  It would be much more difficult for a
portable MPI like MPICH to implement this semantic.  I think the semantic
as defined below remains the right choice.

"In the Fortran version of MPI_GET_PROCESSOR_NAME, the value returned in
name is MPI_MAX_PROCESSOR_NAME characters long,
left-justified and blank-filled.  Resultlen indicates the number of
characters returned, not including any trailing blanks.


               Dick

Dick Treumann                IBM RS/6000 SP Development
Tele (914) 433-7846         Fax (914) 433-8363