MPI_Init(3)                (11/1/1994)                MPI_Init(3)



     NAME
          MPI_Init - Initialize the MPI execution environment


     INPUT PARAMETERS
          argc - Pointer to the number of arguments
          argv - Pointer to the argument vector


     COMMAND LINE ARGUMENTS
          MPI specifies no command-line arguments but does allow an
          MPI implementation to make use of them.

          -mpiqueue
               - print out the state of the message queues when
               MPI_FINALIZE is called.  All processors print; the
               output may be hard to decipher.  This is intended as a
               debugging aid.
          -mpiversion
               - print out the version of the implementation (NOT of
               MPI), including the arguments that were used with
               configure.

          -mpedbg
               - Start a debugger in an xterm window if there is an
               error (either detected by MPI or a normally fatal
               signal).  This works only if MPICH was configured with
               -mpedbg.

          -mpipktsize
               nn - Set the message length where the ADI changed to
               the long message protocol to nn.  This only works if
               MPICH was configured with -var_pkt.

               The following options are available only on the
               Chameleon device and devices built with debugging code.

          -mpichdebug
               - Print out the Chameleon device operations
          -mpichmemdebug
               - (Chameleon device only) Print out a list of
               unreclaimed memory.  This requires that MPI be built
               with the -DMPIR_DEBUG_MEM switch.  This is intended for
               debugging the MPI implementation itself.
          -mpichmsg
               - Print out the number of messages received, by
               category, when the program exits.



     NOTES
          Note that the Fortran binding for this routine has only the



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     MPI_Init(3)                (11/1/1994)                MPI_Init(3)



          error return argument (MPI_INIT(ierror))

          Because the Fortran and C versions of MPI_Init are
          different, there is a restriction on who can call MPI_Init.
          The version (Fortran or C) must match the main program.
          That is, if the main program is in C, then the C version of
          MPI_Init must be called.  If the main program is in Fortran,
          the Fortran version must be called.

          On exit from this routine, all processes will have a copy of
          the argument list.  This is NOT REQUIRED by the MPI
          standard, and truely portable codes should not rely on it.
          This is provided as a service by this implementation (an MPI
          implementation is allowed to distribute the command line
          arguments but is not required to).

          Command line arguments are not provided to Fortran programs.
          More precisely, non-standard Fortran routines such as getarg
          and iargc have undefined behavior in MPI and in this
          implementation.


     SIGNALS USED
          The MPI standard requires that all signals used be
          documented.  The MPICH implementation itself uses no
          signals, but some of the softare that MPICH relies on may
          use some signals.  The list below is partial and should be
          independantly checked if you (and any package that you use)
          depend on particular signals.


     IBM POE/MPL FOR SP2
          SIGHUP, SIGINT, SIGQUIT, SIGFPE, SIGSEGV, SIGPIPE, SIGALRM,
          SIGTERM, SIGIO


     -MPEDBG
          SIGQUIT, SIGILL, SIGFPE, SIGBUS, SIGSEGV, SIGSYS


     SYNOPSIS
          #include "mpi.h"
          int MPI_Init(argc,argv)
          int  *argc;
          char ***argv;



     LOCATION
           init.c





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