Synopsis
int MPI_Init_thread(int *argc, char ***argv, int required, int *provided)Input Parameters
- required
-
desired level of thread support (integer)
Input/Output Parameters
- argc
-
argc (None)
- argv
-
argv (None)
Output Parameters
- provided
-
provided level of thread support (integer)
Command line arguments
MPI specifies no command-line arguments but does allow an MPI
implementation to make use of them. See MPI_INIT for a description of
the command line arguments supported by MPI_INIT and MPI_INIT_THREAD.
Notes
The valid values for the level of thread support are:
-
MPI_THREAD_SINGLE- Only one thread will execute. -
MPI_THREAD_FUNNELED- The process may be multi-threaded, but only the main thread will make MPI calls (all MPI calls are funneled to the main thread). -
MPI_THREAD_SERIALIZED- The process may be multi-threaded, and multiple threads may make MPI calls, but only one at a time: MPI calls are not made concurrently from two distinct threads (all MPI calls are serialized). -
MPI_THREAD_MULTIPLE- Multiple threads may call MPI, with no restrictions.
Notes for Fortran
Note that the Fortran binding for this routine does not have the argc and
argv arguments. (MPI_INIT_THREAD(required, provided, ierror))
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_OTHER - Other error; use 'MPI_Error_string' to get more information about this error code.