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MPI_Comm_get_parent(3) man page (version 1.3.4)

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NAME

       MPI_Comm_get_parent  -  Returns the parent intercommunicator of current
       spawned process.

SYNTAX


C Syntax

       #include <mpi.h>
       int MPI_Comm_get_parent(MPI_Comm *parent)

Fortran Syntax

       INCLUDE 'mpif.h'
       MPI_COMM_GET_PARENT(PARENT, IERROR)
            INTEGER   PARENT, IERROR

C++ Syntax

       #include <mpi.h>
       static MPI::Intercomm MPI::Comm::Get_parent()

OUTPUT PARAMETERS

       parent    The parent communicator (handle).

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       If a process was started with MPI_Comm_spawn  or  MPI_Comm_spawn_multi-
       ple,  MPI_Comm_get_parent returns the "parent" intercommunicator of the
       current process. This parent intercommunicator  is  created  implicitly
       inside  of  MPI_Init  and is the same intercommunicator returned by the
       spawn call made in the parents.

       If  the  process   was   not   spawned,   MPI_Comm_get_parent   returns
       MPI_COMM_NULL.

       After    the    parent   communicator   is   freed   or   disconnected,
       MPI_Comm_get_parent returns MPI_COMM_NULL.

NOTES

       MPI_Comm_get_parent returns a handle  to  a  single  intercommunicator.
       Calling  MPI_Comm_get_parent a second time returns a handle to the same
       intercommunicator.  Freeing  the  handle  with  MPI_Comm_disconnect  or
       MPI_Comm_free  will  cause other references to the intercommunicator to
       become invalid (dangling). Note that calling MPI_Comm_free on the  par-
       ent communicator is not useful.

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.

SEE ALSO

       MPI_Comm_spawn
       MPI_Comm_spawn_multiple

1.3.4                            Nov 11, 2009           MPI_Comm_get_parent(3)

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