MPI_Iprobe(3) MPI MPI_Iprobe(3) NAME MPI_Iprobe - Nonblocking test for a message SYNOPSIS #include "mpi.h" int MPI_Iprobe( int source, int tag, MPI_Comm comm, int *flag, MPI_Status *status ) INPUT PARAMETERS source - source rank, or MPI_ANY_SOURCE (integer) tag - tag value or MPI_ANY_TAG (integer) comm - communicator (handle) OUTPUT PARAMETER flag - (logical) status - status object (Status) NOTES FOR FORTRAN 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. ERRORS 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_Errhandler_set ; the prede- fined 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. MPI_SUCCESS - No error; MPI routine completed successfully. MPI_ERR_COMM - Invalid communicator. A common error is to use a null commu- nicator in a call (not even allowed in MPI_Comm_rank ). MPI_ERR_TAG - Invalid tag argument. Tags must be non-negative; tags in a receive ( MPI_Recv , MPI_Irecv , MPI_Sendrecv , etc.) may also be MPI_ANY_TAG . The largest tag value is available through the the attribute MPI_TAG_UB . MPI_ERR_RANK - Invalid source or destination rank. Ranks must be between zero and the size of the communicator minus one; ranks in a receive ( MPI_Recv , MPI_Irecv , MPI_Sendrecv , etc.) may also be MPI_ANY_SOURCE . LOCATION iprobe.c 12/7/2004 MPI_Iprobe(3)