MPI_Comm_create(3)

1MPI_Comm_create(3)                  LAM/MPI                 MPI_Comm_create(3)
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NAME

6       MPI_Comm_create -  Creates a new communicator
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SYNOPSIS

9       #include <mpi.h>
10       int MPI_Comm_create(MPI_Comm comm, MPI_Group group,
11                          MPI_Comm *newcomm)
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INPUT PARAMETERS

14       comm   - communicator (handle)
15       group  - group, which is a subset of the group of comm (handle)
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OUTPUT PARAMETER

19       newcomm
20              - new communicator (handle)
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NOTES

24       When  a  communicator  is no longer being used, it should be freed with
25       MPI_Comm_free .
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NOTES FOR FORTRAN

30       All MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK )  have
31       an  additional  argument ierr at the end of the argument list.  ierr is
32       an integer and has the same meaning as the return value of the  routine
33       in  C.   In Fortran, MPI routines are subroutines, and are invoked with
34       the call statement.
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36       All MPI objects (e.g., MPI_Datatype , MPI_Comm ) are of type INTEGER in
37       Fortran.
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ERRORS

41       If an error occurs in an MPI function, the current MPI error handler is
42       called to handle it.  By default, this error  handler  aborts  the  MPI
43       job.   The  error  handler may be changed with MPI_Errhandler_set ; the
44       predefined error handler MPI_ERRORS_RETURN may be used to  cause  error
45       values  to  be  returned  (in C and Fortran; this error handler is less
46       useful in with the C++ MPI  bindings.   The  predefined  error  handler
47       MPI::ERRORS_THROW_EXCEPTIONS  should  be used in C++ if the error value
48       needs to be recovered).  Note that MPI does not guarantee that  an  MPI
49       program can continue past an error.
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51       All  MPI  routines  (except  MPI_Wtime  and MPI_Wtick ) return an error
52       value; C routines as the value of the function and Fortran routines  in
53       the  last  argument.  The C++ bindings for MPI do not return error val‐
54       ues; instead, error values are communicated by throwing  exceptions  of
55       type  MPI::Exception  (but not by default).  Exceptions are only thrown
56       if the error value is not MPI::SUCCESS .
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59       Note that if the MPI::ERRORS_RETURN handler is set in  C++,  while  MPI
60       functions  will  return  upon an error, there will be no way to recover
61       what the actual error value was.
62       MPI_SUCCESS
63              - No error; MPI routine completed successfully.
64       MPI_ERR_COMM
65              - Invalid communicator.  A common error is to use a null  commu‐
66              nicator in a call (not even allowed in MPI_Comm_rank ).
67       MPI_ERR_GROUP
68              - Null group passed to function.
69       MPI_ERR_OTHER
70              - This error is returned when some part of the LAM/MPI implemen‐
71              tation is unable to acquire memory.
72       MPI_ERR_INTERN
73              - An internal error has been detected.  This is  fatal.   Please
74              send  a  bug report to the LAM mailing list (see http://www.lam-
75              mpi.org/contact.php ).
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MORE INFORMATION

83       For more information, please see the official MPI Forum web site, which
84       contains  the  text of both the MPI-1 and MPI-2 standards.  These docu‐
85       ments contain detailed information about each  MPI  function  (most  of
86       which is not duplicated in these man pages).
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88       http://www.mpi-forum.org/
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ACKNOWLEDGEMENTS

93       The  LAM Team would like the thank the MPICH Team for the handy program
94       to generate man pages  ("doctext"  from  ftp://ftp.mcs.anl.gov/pub/sow‐
95       ing/sowing.tar.gz  ), the initial formatting, and some initial text for
96       most of the MPI-1 man pages.
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LOCATION

99       ccreate.c
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103LAM/MPI 7.1.2                      2/23/2006                MPI_Comm_create(3)