MPI_Startall
Starts a collection of persistent requests
Synopsis
int MPI_Startall(int count, MPI_Request array_of_requests[])
Input Parameters
- count
- list length (non-negative integer)
Input/Output Parameters
- array_of_requests
- array of requests (handle)
Notes
Unlike MPI_Waitall, MPI_Startall does not provide a mechanism for
returning multiple errors nor pinpointing the request(s) involved.
Furthermore, the behavior of MPI_Startall after an error occurs is not
defined by the MPI standard. If well-defined error reporting and behavior
are required, multiple calls to MPI_Start should be used instead.
Thread and Interrupt Safety
This routine is thread-safe. This means that this routine may be
safely used by multiple threads without the need for any user-provided
thread locks. However, the routine is not interrupt safe. Typically,
this is due to the use of memory allocation routines such as malloc
or other non-MPICH runtime routines that are themselves not interrupt-safe.
Notes for Fortran
All MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK) have
an additional argument ierr at the end of the argument list. ierr
is an integer and has the same meaning as the return value of the routine
in C. In Fortran, MPI routines are subroutines, and are invoked with the
call statement.
All MPI objects (e.g., MPI_Datatype, MPI_Comm) are of type INTEGER
in Fortran.
Errors
All MPI routines (except MPI_Wtime and MPI_Wtick) return an error value;
C routines as the value of the function and Fortran routines in the last
argument. Before the value is returned, the current MPI error handler is
called. By default, this error handler aborts the MPI job. The error handler
may be changed with MPI_Comm_set_errhandler (for communicators),
MPI_File_set_errhandler (for files), and MPI_Win_set_errhandler (for
RMA windows). The MPI-1 routine MPI_Errhandler_set may be used but
its use is deprecated. 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; however, MPI implementations will attempt to continue whenever
possible.
- MPI_SUCCESS
- No error; MPI routine completed successfully.
- MPI_ERR_COUNT
- Invalid count argument. Count arguments must be
non-negative; a count of zero is often valid.
- MPI_ERR_REQUEST
- Invalid MPI_Request. Either null or, in the case of a
MPI_Start or MPI_Startall, not a persistent request.
- MPI_ERR_OTHER
- Other error; use MPI_Error_string to get more information
about this error code.