NAME

       MPI_Testall - Tests for the completion of all previously initiated communications in a list.

SYNTAX

C Syntax

       #include <mpi.h>
       int MPI_Testall(int count, MPI_Request array_of_requests[],
            int *flag, MPI_Status array_of_statuses[])

Fortran Syntax

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

Fortran 2008 Syntax

       USE mpi_f08
       MPI_Testall(count, array_of_requests, flag, array_of_statuses, ierror)
            INTEGER, INTENT(IN) :: count
            TYPE(MPI_Request), INTENT(INOUT) :: array_of_requests(count)
            LOGICAL, INTENT(OUT) :: flag
            TYPE(MPI_Status) :: array_of_statuses(*)
            INTEGER, OPTIONAL, INTENT(OUT) :: ierror

C++ Syntax

       #include <mpi.h>
       static bool Request::Testall(int count, Request
            array_of_requests[], Status array_of_statuses[])

       static bool Request::Testall(int count, Request array_of_requests[])

INPUT PARAMETERS

       count     Lists length (integer).

       array_of_requests
                 Array of requests (array of handles).

OUTPUT PARAMETERS

       flag      True if previously initiated communications are complete (logical.)

       array_of_statuses
                 Array of status objects (array of status).

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       Returns  flag  =  true  if  all communications associated with active handles in the array have completed
       (this includes the case where no handle in the list is active). In this  case,  each  status  entry  that
       corresponds  to  an active handle request is set to the status of the corresponding communication; if the
       request was allocated by a nonblocking communication call then it is deallocated, and the handle  is  set
       to MPI_REQUEST_NULL. Each status entry that corresponds to a null or inactive handle is set to empty.

       Otherwise,  flag  =  false  is  returned, no request is modified and the values of the status entries are
       undefined. This is a local operation.

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

       Errors  that  occurred  during  the  execution of MPI_Testall are handled in the same manner as errors in
       MPI_Waitall.

NOTE

       flag is true only if all requests have completed. Otherwise, flag is false, and neither array_of_requests
       nor array_of_statuses is modified.

ERRORS

       For each invocation of MPI_Testall, if one or more requests generate an MPI exception, only the first MPI
       request that caused an exception will be passed to its  corresponding  error  handler.   No  other  error
       handlers  will  be  invoked (even if multiple requests generated exceptions).  However, all requests that
       generate an exception will have a relevant error code set in  the  corresponding  status.MPI_ERROR  field
       (unless MPI_STATUSES_IGNORE was used).

       The  default  error  handler aborts the MPI job, except for I/O function errors. The error handler may be
       changed with MPI_Comm_set_errhandler, MPI_File_set_errhandler, or  MPI_Win_set_errhandler  (depending  on
       the  type  of  MPI handle that generated the MPI request); 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.

       If the invoked error handler allows MPI_Testall to return to the caller, the value MPI_ERR_IN_STATUS will
       be   returned   in   the   C   and   Fortran   bindings.    In  C++,  if  the  predefined  error  handler
       MPI::ERRORS_THROW_EXCEPTIONS  is  used,  the  value  MPI::ERR_IN_STATUS  will   be   contained   in   the
       MPI::Exception  object.   The  MPI_ERROR  field can then be examined in the array of returned statuses to
       determine exactly which request(s) generated an exception.

SEE ALSO

       MPI_Comm_set_errhandler
       MPI_File_set_errhandler
       MPI_Test
       MPI_Testany
       MPI_Testsome
       MPI_Wait
       MPI_Waitall
       MPI_Waitany
       MPI_Waitsome
       MPI_Win_set_errhandler

4.1.6                                             Sep 30, 2023                                    MPI_Testall(3)