MPI_Comm_get_name - Return the print name from the communicator
int MPI_Comm_get_name(MPI_Comm comm, char *comm_name, int *resultlen)
- comm
- - Communicator to get name of (handle)
- comm_name
- - On output, contains the name of the communicator. It must be an array of
size at least MPI_MAX_OBJECT_NAME .
- resultlen
- - Number of characters in name
Because MPI specifies that null objects (e.g., MPI_COMM_NULL ) are
invalid as input to MPI routines unless otherwise specified, using
MPI_COMM_NULL as input to this routine is an error.
This routine is thread and interrupt safe only if no MPI routine that updates or
frees the same MPI object may be called concurrently with this routine.
The MPI standard defined a thread-safe interface but this does not
mean that all routines may be called without any thread locks. For example,
two threads must not attempt to change the contents of the same
MPI_Info object concurrently. The user is responsible in this case
for using some mechanism, such as thread locks, to ensure that only one
thread at a time makes use of this routine.
All MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK )
have an additional argument ierr at the end of the argument list.
ierr is an integer and has the same meaning as the return value of the
routine in C. In Fortran, MPI routines are subroutines, and are invoked with
the call statement.
All MPI objects (e.g., MPI_Datatype , MPI_Comm ) are
of type INTEGER in Fortran.
All MPI routines (except MPI_Wtime and MPI_Wtick ) return an error
value; C routines as the value of the function and Fortran routines in the
last argument. Before the value is returned, the current MPI error handler is
called. By default, this error handler aborts the MPI job. The error handler
may be changed with MPI_Comm_set_errhandler (for communicators),
MPI_File_set_errhandler (for files), and MPI_Win_set_errhandler
(for RMA windows). The MPI-1 routine MPI_Errhandler_set may be used but
its use is deprecated. The predefined error handler MPI_ERRORS_RETURN
may be used to cause error values to be returned. Note that MPI does
not guarantee that an MPI program can continue past an error; however,
MPI implementations will attempt to continue whenever possible.
- MPI_SUCCESS
- - No error; MPI routine completed successfully.
- MPI_ERR_COMM
- - Invalid communicator. A common error is to use a null communicator in a
call (not even allowed in MPI_Comm_rank ).