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mpi_comm_get_name(3openmpi) [osx man page]

MPI_Comm_get_name(3OpenMPI)											       MPI_Comm_get_name(3OpenMPI)

NAME

       MPI_Comm_get_name - Returns the name that was most recently associated with a communicator.

SYNTAX

C Syntax
       #include <mpi.h>
       int MPI_Comm_get_name(MPI_Comm comm, char *comm_name, int *resultlen)

Fortran Syntax
       INCLUDE 'mpif.h'
       MPI_COMM_GET_NAME(COMM, COMM_NAME, RESULTLEN, IERROR)
	    INTEGER   COMM, RESULTLEN, IERROR
	    CHARACTER*(*) COMM_NAME

C++ Syntax
       #include <mpi.h>
       void MPI::Comm::Get_name(char* comm_name, int& resultlen) const

INPUT PARAMETER

       comm	 Communicator the name of which is to be returned (handle).

       OUTPUT PARAMETER

       comm_name Name previously stored on the communicator, or an empty string if no such name exists (string).

       resultlen Length of returned name (integer).

       IERROR	 Fortran only: Error status (integer).

DESCRIPTION

       MPI_Comm_get_name  returns the last name that was previously associated with the given communicator. The name may be set and retrieved from
       any language. The same name will be returned independent of the language used. comm_name should be allocated so that it can hold a  result-
       ing string of length MPI_MAX_OBJECT_NAME characters. MPI_Comm_get_name returns a copy of the set name in comm_name.

       If the user has not associated a name with a communicator, or an error occurs, MPI_Comm_get_name will return an empty string (all spaces in
       Fortran, "" in C and C++). The three predefined communicators will  have  predefined  names  associated	with  them.  Thus,  the  names	of
       MPI_COMM_WORLD,	MPI_COMM_SELF,	and  MPI_COMM_PARENT will have the default of MPI_COMM_WORLD, MPI_COMM_SELF, and MPI_COMM_PARENT. The fact
       that the system may have chosen to give a default name to a communicator does not prevent the user from setting a name on the same communi-
       cator; doing this removes the old name and assigns the new one.

NOTES

       It is safe simply to print the string returned by MPI_Comm_get_name, as it is always a valid string even if there was no name.

       Note  that  associating	a  name  with a communicator has no effect on the semantics of an MPI program, and will (necessarily) increase the
       store requirement of the program, since the names must be saved. Therefore, there is no requirement that users use these functions to asso-
       ciate names with communicators. However debugging and profiling MPI applications may be made easier if names are associated with communica-
       tors, since the debugger or profiler should then be able to present information in a less cryptic manner.

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.

Open MPI 1.2							  September 2006				       MPI_Comm_get_name(3OpenMPI)

Check Out this Related Man Page

MPI_Comm_get_name(3)							MPI						      MPI_Comm_get_name(3)

NAME

       MPI_Comm_get_name -  Return the print name from the communicator

SYNOPSIS

       int MPI_Comm_get_name(MPI_Comm comm, char *comm_name, int *resultlen)

INPUT PARAMETER

       comm   - Communicator to get name of (handle)

OUTPUT PARAMETERS

       comm_name
	      - On output, contains the name of the communicator.  It must be an array of size at least MPI_MAX_OBJECT_NAME .

       resultlen
	      - Number of characters in name

NOTES

       Because	MPI  specifies	that  null  objects  (e.g., MPI_COMM_NULL ) are invalid as input to MPI routines unless otherwise specified, using
       MPI_COMM_NULL as input to this routine is an error.

THREAD AND INTERRUPT SAFETY

       This routine is thread and interrupt safe only if no MPI routine that updates or frees the same MPI object may be called concurrently  with
       this routine.

       The  MPI  standard  defined  a  thread-safe interface but this does not mean that all routines may be called without any thread locks.  For
       example, two threads must not attempt to change the contents of the same MPI_Info object concurrently.  The user  is  responsible  in  this
       case for using some mechanism, such as thread locks, to ensure that only one thread at a time makes use of this routine.

NOTES FOR FORTRAN

       All  MPI  routines in Fortran (except for MPI_WTIME and MPI_WTICK ) have an additional argument ierr at the end of the argument list.  ierr
       is an integer and has the same meaning as the return value of the routine in C.	In Fortran, MPI routines are subroutines, and are  invoked
       with the call statement.

       All MPI objects (e.g., MPI_Datatype , MPI_Comm ) are of type INTEGER in Fortran.

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 guarentee 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_COMM
	      - Invalid communicator.  A common error is to use a null communicator in a call (not even allowed in MPI_Comm_rank ).

LOCATION

       comm_get_name.c

								     7/28/2010						      MPI_Comm_get_name(3)
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