NAME
          pnet_setup - Initialize communication pattern

     SYNOPSIS
          #include <mpi.h>
          #include "pnet.h"

          int pnet_setup(Pnet *pnet);

     DESCRIPTION
          Function initializes communication pattern necessary for the
          distributed network. This is the core function of the Pnet
          library. Pnet has to be initialized by pnet_init and
          connections have to be added by calls of pnet_addconnect
          before pnet_setup can be called. Data have to be exchanged
          by invoking the pnet_exchg macro. After calling this
          function connections must not be added.  The argument of
          pnet_setup is:

          pnet Pointer to initialized Pnet struct

     RETURN VALUE
          Upon successful completion PNET_OK is returned.

     ERRORS
          PNET_ALLOC_ERR
               Cannot allocate memory.


     AUTHORS
          For authors and contributors see AUTHORS file


     COPYRIGHT
          (C) Potsdam Institute for Climate Impact Research (PIK), see
          COPYRIGHT file


     SEE ALSO
          pnet_exchg(3), pnet_init(3), pnet_addconnect(3),
          pnet_free(3),  pnet_lo(3), pnet_hi(3), pnet_nodes(3)