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


C Syntax

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

Fortran Syntax

       INCLUDE 'mpif.h'
            CHARACTER*(*) COMM_NAME

C++ Syntax

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


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


       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).


       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  resulting  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 communicator; doing this removes the old name and assigns the new one.


       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
       associate  names  with communicators. However debugging and profiling MPI applications may
       be made easier if names are associated with communicators, since the debugger or  profiler
       should then be able to present information in a less cryptic manner.


       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.