mpi_init(3openmpi) [osx man page]

MPI_Init(3OpenMPI)														MPI_Init(3OpenMPI)

NAME

       MPI_Init - Initializes the MPI execution environment

SYNTAX

C Syntax
       #include <mpi.h>
       int MPI_Init(int *argc, char ***argv)

Fortran Syntax
       INCLUDE 'mpif.h'
       MPI_INIT(IERROR)
	    INTEGER   IERROR

C++ Syntax
       #include <mpi.h>
       void MPI::Init(int& argc, char**& argv)
       void MPI::Init()

INPUT PARAMETERS

       argc	 C/C++ only: Pointer to the number of arguments.

       argv	 C/C++ only: Argument vector.

OUTPUT PARAMETER

       IERROR	 Fortran only: Error status (integer).

DESCRIPTION

       This  routine,  or MPI_Init_thread, must be called before any other MPI routine (apart from MPI_Initialized) is called. MPI can be initial-
       ized at most once; subsequent calls to MPI_Init or MPI_Init_thread are erroneous.

       All MPI programs must contain a call to MPI_Init or MPI_Init_thread. Open MPI accepts the C/C++ argc and argv arguments to main,  but  nei-
       ther modifies, interprets, nor distributes them:

	    {
		 /* declare variables */
		 MPI_Init(&argc, &argv);
		 /* parse arguments */
		 /* main program */
		 MPI_Finalize();
	    }

NOTES

       The Fortran version does not have provisions for argc and argv and takes only IERROR.

       The  MPI Standard does not say what a program can do before an MPI_Init or after an MPI_Finalize. In the Open MPI implementation, it should
       do as little as possible. In particular, avoid anything that changes the external state of the program,	such  as  opening  files,  reading
       standard input, or writing to standard output.

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 the MPI man page for a full list of MPI error codes.

SEE ALSO

       MPI_Init_thread
       MPI_Initialized
       MPI_Finalize

Open MPI 1.2							  September 2006						MPI_Init(3OpenMPI)

MPI_Init_thread(3)							MPI							MPI_Init_thread(3)

NAME

       MPI_Init_thread -  Initialize the MPI execution environment

SYNOPSIS

       int MPI_Init_thread( int *argc, char ***argv, int required, int *provided )

INPUT PARAMETERS

       argc   - Pointer to the number of arguments
       argv   - Pointer to the argument vector
       required
	      - Level of desired thread support

OUTPUT PARAMETER

       provided
	      - Level of provided thread support

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 concur-
	      rently 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) )

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 guarentee 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.

SEE ALSO

       MPI_Init, MPI_Finalize

LOCATION

       initthread.c

								     6/18/2011							MPI_Init_thread(3)