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MPI_Startall(3) man page (version 1.3.4)

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NAME

       MPI_Startall - Starts a collection of requests.

SYNTAX


C Syntax

       #include <mpi.h>
       int MPI_Startall(int count, MPI_Request *array_of_requests)

Fortran Syntax

       INCLUDE 'mpif.h'
       MPI_STARTALL(COUNT, ARRAY_OF_REQUESTS, IERROR)
            INTEGER   COUNT, ARRAY_OF_REQUESTS(*), IERROR

C++ Syntax

       #include <mpi.h>
       static void Prequest::Startall(int count, Prequest array_of_requests[])

INPUT PARAMETER

       count     List length (integer).

INPUT/OUTPUT PARAMETER

       array_of_requests
                 Array of requests (array of handle).

OUTPUT PARAMETER

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       Starts    all    communications    associated    with    requests    in
       array_of_requests. A call  to   MPI_Startall(count,  array_of_requests)
       has the same effect as calls to MPI_Start (&array_of_requests[i]), exe-
       cuted for i=0 ,..., count-1, in some arbitrary order.

       A communication started with a call to  MPI_Start  or  MPI_Startall  is
       completed  by a call to MPI_Wait, MPI_Test, or one of the derived func-
       tions MPI_Waitany, MPI_Testany, MPI_Waitall, MPI_Testall, MPI_Waitsome,
       MPI_Testsome  (these  are described in Section 3.7.5 of the MPI-1 Stan-
       dard, "Multiple Completions"). The request becomes inactive after  suc-
       cessful  completion by such a call. The request is not deallocated, and
       it can be activated anew by another MPI_Start or MPI_Startall call.

       A persistent request is deallocated by a call to MPI_Request_free  (see
       Section 3.7.3  of the MPI-1 Standard, "Communication Completion").

       The  call  to  MPI_Request_free  can  occur at any point in the program
       after the persistent request was created. However, the request will  be
       deallocated  only  after  it  becomes inactive. Active receive requests
       should not be freed. Otherwise, it will not be possible to  check  that
       the  receive  has  completed.  It  is  preferable,  in general, to free
       requests when they are inactive. If this rule  is  followed,  then  the
       persistent  communication  request  functions  will  be  invoked  in  a
       A send operation initiated with  MPI_Start  can  be  matched  with  any
       receive  operation  and,  likewise,  a receive operation initiated with
       MPI_Start can receive messages generated by any send operation.

ERRORS

       Almost all MPI routines return an error value; C routines as the  value
       of  the  function  and Fortran routines in the last argument. C++ func-
       tions do not return errors. If the default  error  handler  is  set  to
       MPI::ERRORS_THROW_EXCEPTIONS, then on error the C++ exception mechanism
       will be used to throw an MPI:Exception object.

       Before the error value is returned, the current MPI  error  handler  is
       called.  By  default, this error handler aborts the MPI job, except for
       I/O  function  errors.  The  error  handler   may   be   changed   with
       MPI_Comm_set_errhandler; 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.

SEE ALSO

       MPI_Bsend_init
       MPI_Rsend_init
       MPI_Send_init
       MPI_Ssend_init
       MPI_Recv_init
       MPI_Start
       MPI_Request_free

1.3.4                            Nov 11, 2009                  MPI_Startall(3)

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