NAME

       MPI_Init -  Initialize the MPI execution environment

SYNOPSIS

       int MPI_Init(int *argc, char ***argv)

INPUT/OUTPUT PARAMETERS

       argc   - argc (None)
       argv   - argv (None)

NOTES

       The  MPI  standard  does  not  say  what  a  program can do before an MPI_INIT or after an
       MPI_FINALIZE .  In the MPICH implementation, you 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.

THREAD AND SIGNAL SAFETY

       This routine must be called by one thread only.  That thread is called the main thread and
       must be the thread that calls MPI_Finalize .

NOTES FOR C

       As  of  MPI-2,  MPI_Init  will  accept  NULL as input parameters. Doing so will impact the
       values stored in MPI_INFO_ENV .

NOTES FOR FORTRAN

       The Fortran binding for MPI_Init has only the error return
       subroutine MPI_INIT(ierr)
       integer ierr

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.

SEE ALSO

       MPI_Init_thread, MPI_Finalize

                                            2/22/2022                                 MPI_Init(3)