From: Jeff Squyres Date: January 23, 2008 6:16:23 AM CST To: mpi-21@XXXXXXXXXXXXX Cc: mpi-21@XXXXXXXXXXX Subject: Re: [mpi-21] Ballot 4 proposal: INOUT arguments Reply-To: mpi-21@XXXXXXXXXXXXX This would be in accordance with the existing MPI-1:2.2 language, and therefore (I think) redundant. However, see my summary e-mail from last night about the C++ bindings -- I am wondering why the special case for [IN]OUT handle arguments exists to begin with (that a parameter is OUT if the underlying MPI object is changed when the handle is not). On Jan 22, 2008, at 11:29 AM, Rolf Rabenseifner wrote: > An alternative-proposal would be to add a clarifying sentence in > Terms and Conventions, MPI-2.0 Sect. 2.5.1, page 9, line 7: > Handle arguments can be marked at INOUT to indicate that the handle > itself may be changed by the routine (e.g., in MPI_TYPE_COMMIT), > or to indicate that the object referenced by the handle may be > changed but the handle itself is kept unchanged > (e.g., MPI_TYPE_SET_NAME). > > Rolf Rabenseifner > > > On Mon, 21 Jan 2008 09:42:02 -0500 > Jeff Squyres wrote:>> This is not already on Bill's errata page. >> >> Proposal: change the INOUT designation of the MPI handle >> parameters in several MPI-2 functions to be IN, because the >> values of the handles are not changing. Only the underlying MPI >> objects are changing. The C bindings for each of these functions >> do *not* pass the MPI handle by reference, therefore disallowing >> the possibility of these parameters actually being INOUT. By the >> same argument, the C++ methods for these functions should be >> const since the C++ object invoking the method will not be changed. >> >> The functions in question are: >> >> MPI_*_SET_NAME for communicators, datatypes, windows >> MPI_*_SET_ATTR for communicators, datatypes, windows >> MPI_*_SET_ERRHANDLER for communicators, files, windows >> >> Locations of specific text to be changed (INOUT -> IN, add "const" >> to C ++ methods): >> >> MPI_COMM_SET_NAME: MPI-2:8.4, p177:35,44 >> MPI-2:A.8.5, p336:28 >> MPI_TYPE_SET_NAME: MPI-2:8.4, p179:41, p180:2 >> MPI-2:A.8.5, p337:2 >> MPI_WIN_SET_NAME: MPI-2:8.4, p181:25,35 >> MPI-2:A.8.5, p337:36 >> >> MPI_COMM_SET_ATTR: MPI-2:8.8.1, p201:6,17 >> MPI-2:A.8.5, p336:27 >> MPI_WIN_SET_ATTR: MPI-2:8.8.2, p204:2,12 >> MPI-2:A.8.5, p337:35 >> MPI_TYPE_SET_ATTR: MPI-2:8.8.3, p206:26,37 >> MPI-2:A.8.5, p337:1 >> >> MPI_COMM_SET_ERRHANDLER: MPI-2:4.13.1, p62:35,43 >> MPI-2:A.8.1, p331:38 >> MPI_WIN_SET_ERRHANDLER: MPI-2:4.13.2, p64:2,10 >> MPI-2:A.8.1, p333:13 >> MPI_FILE_SET_ERRHANDLER: MPI-2:4.13.3, p65:14,22 >> MPI-2:A.8.1, p332:34 >> >> NOTE: The "const" issues of this proposal will be dependent upon a >> 2nd proposal about re-instituting the "const" on MPI predefined >> handles that was removed in ballot 2. >> >> -- >> Jeff Squyres >> Cisco Systems >> > > > > Dr. Rolf Rabenseifner . . . . . . . . . .. email rabenseifner@XXXXXXX > High Performance Computing Center (HLRS) . phone ++49(0)711/685-65530 > University of Stuttgart . . . . . . . . .. fax ++49(0)711 / 685-65832 > Head of Dpmt Parallel Computing . . . www.hlrs.de/people/rabenseifner > Nobelstr. 19, D-70550 Stuttgart, Germany . (Office: Allmandring 30) > -- Jeff Squyres Cisco Systems