bionic (3) MPI_Test.3.gz

NAME

       MPI_Test -  Tests for the completion of a request

SYNOPSIS

       int MPI_Test(MPI_Request *request, int *flag, MPI_Status *status)

INPUT PARAMETERS

       request
              - MPI request (handle)

OUTPUT PARAMETERS

       flag   - true if operation completed (logical)
       status - status object (Status).  May be MPI_STATUS_IGNORE .

THREAD AND INTERRUPT SAFETY

       This routine is thread-safe.  This means that this routine may be safely used by multiple threads without
       the need for any user-provided thread locks.  However, the routine is  not  interrupt  safe.   Typically,
       this  is  due to the use of memory allocation routines such as malloc or other non-MPICH runtime routines
       that are themselves not interrupt-safe.

NOTES ON THE MPI_STATUS ARGUMENT

       The MPI_ERROR field  of  the  status  return  is  only  set  if  the  return  from  the  MPI  routine  is
       MPI_ERR_IN_STATUS  .   That  error  class  is  only returned by the routines that take an array of status
       arguments ( MPI_Testall , MPI_Testsome , MPI_Waitall , and MPI_Waitsome ).  In all other cases, the value
       of  the  MPI_ERROR  field in the status is unchanged.  See section 3.2.5 in the MPI-1.1 specification for
       the exact text.

       For send operations, the only use of status is for MPI_Test_cancelled or in the case  that  there  is  an
       error  in  one of the four routines that may return the error class MPI_ERR_IN_STATUS , in which case the
       MPI_ERROR field of status will be set.  In that case, the value will be set to MPI_SUCCESS for  any  send
       or  receive operation that completed successfully, or MPI_ERR_PENDING for any operation which has neither
       failed nor completed.

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.

       The  status  argument  must  be  declared  as  an  array  of  size  MPI_STATUS_SIZE  ,  as   in   integer
       status(MPI_STATUS_SIZE) .

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_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 guarentee 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_REQUEST
              - Invalid MPI_Request .  Either null or, in the case of  a  MPI_Start  or  MPI_Startall  ,  not  a
              persistent request.
       MPI_ERR_ARG
              -  Invalid  argument.   Some  argument  is invalid and is not identified by a specific error class
              (e.g., MPI_ERR_RANK ).

                                                   11/12/2016                                        MPI_Test(3)