mpi_initialized(3openmpi) [osx man page]

MPI_Initialized(3OpenMPI)												 MPI_Initialized(3OpenMPI)

NAME

       MPI_Initialized - Indicates whether MPI_Init has been called.

SYNTAX

C Syntax
       #include <mpi.h>
       int MPI_Initialized(int *flag)

Fortran Syntax
       INCLUDE 'mpif.h'
       MPI_INITIALIZED(FLAG, IERROR)
	    LOGICAL   FLAG
	    INTEGER   IERROR

C++ Syntax
       #include <mpi.h>
       bool Is_initialized()

OUTPUT PARAMETERS

       flag	 Flag is true if MPI_Init has been called and false otherwise.

       IERROR	 Fortran only: Error status (integer).

DESCRIPTION

       This  routine  may  be  used  to  determine  whether MPI_Init has been called. It is the only routine that may be called before MPI_Init is
       called.

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_Init

Open MPI 1.2							  September 2006					 MPI_Initialized(3OpenMPI)

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)