70 строки
2.6 KiB
Groff
70 строки
2.6 KiB
Groff
.\"Copyright 2006, Sun Microsystems, Inc. All rights reserved. Use is subject to license terms.
|
|
.\" Copyright (c) 1996 Thinking Machines Corporation
|
|
.TH MPI_Start 3OpenMPI "September 2006" "Open MPI 1.2" " "
|
|
.SH NAME
|
|
\fBMPI_Start\fP \- Initiates a communication using a persistent request handle.
|
|
|
|
.SH SYNTAX
|
|
.ft R
|
|
.SH C Syntax
|
|
.nf
|
|
#include <mpi.h>
|
|
int MPI_Start(MPI_Request *\fIrequest\fP)
|
|
|
|
.SH Fortran Syntax
|
|
.nf
|
|
INCLUDE 'mpif.h'
|
|
MPI_START(\fIREQUEST, IERROR\fP)
|
|
INTEGER \fIREQUEST, IERROR\fP
|
|
|
|
.SH C++ Syntax
|
|
.nf
|
|
#include <mpi.h>
|
|
void Prequest::Start()
|
|
|
|
.SH INPUT PARAMETER
|
|
.ft R
|
|
.TP 1i
|
|
request
|
|
Communication request (handle).
|
|
|
|
.SH OUTPUT PARAMETER
|
|
.ft R
|
|
.TP 1i
|
|
IERROR
|
|
Fortran only: Error status (integer).
|
|
|
|
.SH DESCRIPTION
|
|
.ft R
|
|
A communication (send or receive) that uses a persistent request is initiated by the function MPI_Start.
|
|
.sp
|
|
The argument, request, is a handle returned by one of the persistent communication-request initialization functions (MPI_Send_init, MPI_Bsend_init, MPI_Ssend_init, MPI_Rsend_init, MPI_Recv_init). The associated request should be inactive and becomes active once the call is made.
|
|
.sp
|
|
If the request is for a send with ready mode, then a matching receive should be posted before the call is made. From the time the call is made until after the operation completes, the communication buffer should not be accessed.
|
|
.sp
|
|
The call is local, with semantics similar to the nonblocking communication operations (see Section 3.7 in the MPI-1 Standard, "Nonblocking Communication.") That is, a call to MPI_Start with a request created by MPI_Send_init starts a communication in the same manner as a call to MPI_Isend; a call to MPI_Start with a request created by MPI_Bsend_init starts a communication in the same manner as a call to MPI_Ibsend; and so on.
|
|
|
|
.SH 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++ functions 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.
|
|
.sp
|
|
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.
|
|
|
|
.SH SEE ALSO
|
|
.ft R
|
|
.sp
|
|
MPI_Bsend_init
|
|
.br
|
|
MPI_Rsend_init
|
|
.br
|
|
MPI_Send_init
|
|
.br
|
|
MPI_Sssend_init
|
|
.br
|
|
MPI_Recv_init
|
|
.br
|
|
MPI_Startall
|
|
|
|
|
|
' @(#)MPI_Start.3 1.20 06/03/09
|