17.2.317. MPI_Request_get_status_any

MPI_Request_get_status_any — Access information associated with an array of requests without freeing the requests.

17.2.317.1. SYNTAX

17.2.317.1.1. C Syntax

int MPI_Request_get_status_any(int count, const MPI_Request
    array_of_requests[], int* index, int* flag, MPI_Status* status)

17.2.317.1.2. Fortran Syntax

USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_REQUEST_GET_STATUS_ANY(COUNT, ARRAY_OF_REQUESTS, INDEX, FLAG, STATUS, IERROR)
    INTEGER COUNT, ARRAY_OF_REQUESTS(*), INDEX, STATUS(MPI_STATUS_SIZE), IERROR
    LOGICAL FLAG

17.2.317.1.3. Fortran 2008 Syntax

USE mpi_f08
MPI_Request_get_status_any(count, array_of_requests, index, flag, status, ierror)
    INTEGER, INTENT(IN) :: count
    TYPE(MPI_Request), INTENT(IN) :: array_of_requests(count)
    INTEGER, INTENT(OUT) :: index
    LOGICAL, INTENT(OUT) :: flag
    TYPE(MPI_Status) :: status
    INTEGER, OPTIONAL, INTENT(OUT) :: ierror

17.2.317.2. INPUT PARAMETERS

  • count: List length (non-negative integer)

  • array_of_requests: Array of requests (array of handles).

17.2.317.3. OUTPUT PARAMETERS

  • index: Index of operation that completed (integer).

  • flag: Boolean flag, same as from MPI_Test (logical).

  • status: MPI_Status object if flag is true (status).

  • ierror: Fortran only: Error status (integer).

17.2.317.4. DESCRIPTION

MPI_Request_get_status_any sets flag = true if either one of the operations associated with active handles has completed. In this case it returns in index the index of this request in the array and the status of the operation in status. It does not deallocate or deactivate the request; a subsequent call to any of the MPI test, wait, or free routines should be executed with that request.

If no operation completed, it returns flag = false and a value of MPI_UNDEFINED in index. status is undefined in this scenario.

If array_of_requests contains no active handles then the call returns immediately with flag = true, index = MPI_UNDEFINED, and an empty status.

If your application does not need to examine the status field, you can save resources by using the predefined constant MPI_STATUS_IGNORE as a special value for the status argument.

17.2.317.5. ERRORS

Almost all MPI routines return an error value; C routines as the return result of the function and Fortran routines in the last argument.

Before the error value is returned, the current MPI error handler associated with the communication object (e.g., communicator, window, file) is called. If no communication object is associated with the MPI call, then the call is considered attached to MPI_COMM_SELF and will call the associated MPI error handler. When MPI_COMM_SELF is not initialized (i.e., before MPI_Init/MPI_Init_thread, after MPI_Finalize, or when using the Sessions Model exclusively) the error raises the initial error handler. The initial error handler can be changed by calling MPI_Comm_set_errhandler on MPI_COMM_SELF when using the World model, or the mpi_initial_errhandler CLI argument to mpiexec or info key to MPI_Comm_spawn/MPI_Comm_spawn_multiple. If no other appropriate error handler has been set, then the MPI_ERRORS_RETURN error handler is called for MPI I/O functions and the MPI_ERRORS_ABORT error handler is called for all other MPI functions.

Open MPI includes three predefined error handlers that can be used:

  • MPI_ERRORS_ARE_FATAL Causes the program to abort all connected MPI processes.

  • MPI_ERRORS_ABORT An error handler that can be invoked on a communicator, window, file, or session. When called on a communicator, it acts as if MPI_Abort was called on that communicator. If called on a window or file, acts as if MPI_Abort was called on a communicator containing the group of processes in the corresponding window or file. If called on a session, aborts only the local process.

  • MPI_ERRORS_RETURN Returns an error code to the application.

MPI applications can also implement their own error handlers by calling:

Note that MPI does not guarantee that an MPI program can continue past an error.

See the MPI man page for a full list of MPI error codes.

See the Error Handling section of the MPI-4.1 standard for more information.