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

       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

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