NAME

       MPI_Initialized - Checks whether MPI has been initialized

SYNTAX

C Syntax

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

Fortran Syntax

       USE MPI
       ! or the older form: INCLUDE 'mpif.h'
       MPI_INITIALIZED(FLAG, IERROR)
            LOGICAL   FLAG
            INTEGER   IERROR

Fortran 2008 Syntax

       USE mpi_f08
       MPI_Initialized(flag, ierror)
            LOGICAL, INTENT(OUT) :: flag
            INTEGER, OPTIONAL, INTENT(OUT) :: ierror

C++ Syntax

       #include <mpi.h>
       bool Is_initialized()

OUTPUT PARAMETERS

       flag      True if MPI has been initialized, and false otherwise (logical).

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       This  routine  may be used to determine whether MPI has been initialized.  It is one of a small number of
       routines that may be called before MPI is initialized and after MPI has been finalized (MPI_Finalized  is
       another).

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.

       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
       MPI_Init_thread
       MPI_Finalize
       MPI_Finalized

4.1.6                                             Sep 30, 2023                                MPI_Initialized(3)