[OMPI users] Client/Server test

[Alberto Giannetti]

I want to connect two MPI programs through the MPI_Comm_connect/ 
MPI_Comm_Accept API.
This is my server app:

int main(int argc, char* argv[])
{
  int rank, count;
  int i;
  float data[100];
  char myport[MPI_MAX_PORT_NAME];
  MPI_Status status;
  MPI_Comm intercomm;
  MPI_Init(&argc, &argv);
  MPI_Comm_rank(MPI_COMM_WORLD, &rank);
  printf("Processor %d (%d, Receiver) initialized\n", rank, getpid());

  MPI_Open_port(MPI_INFO_NULL, myport);
  printf("Opened port %s\n", myport);

  printf("Waiting for connections on %s...\n", myport);
  MPI_Comm_accept(myport, MPI_INFO_NULL, 0, MPI_COMM_SELF, &intercomm);
  printf("New connection on port %s\n", myport);

  printf("Processor %d waiting for data from new intercomm...\n",  
rank);
  MPI_Recv(data, 100, MPI_FLOAT, MPI_ANY_SOURCE, MPI_ANY_TAG,  
intercomm, &status);
  MPI_Get_count(&status, MPI_FLOAT, &count);
  printf("Processor %d got %d elements: %f, %f, %f...\n", rank,  
count, data[0], data[1], data[2]);

  MPI_Finalize();
}


And my client program:

int main(int argc, char* argv[])
{
  int rank, i;
  float data[100];
  char myport[MPI_MAX_PORT_NAME];
  MPI_Comm intercomm;

  MPI_Init(&argc, &argv);
  MPI_Comm_rank(MPI_COMM_WORLD, &rank);
  printf("Processor %d (%d, Sender) initialized\n", rank, getpid());

  if( argc < 2 ) {
    fprintf(stderr, "Require server port name\n");
    MPI_Finalize();
    exit(-1);
  }

  for( i = 0; i < 100; i++ )
    data[i] = i;

  strcpy(myport, argv[1]);
  printf("Processor %d connecting to '%s'\n", rank, myport);
  MPI_Comm_connect(myport, MPI_INFO_NULL, 0, MPI_COMM_SELF,  
&intercomm);

  printf("Processor %d sending data through intercomm...\n", rank);
  MPI_Send(data, 100, MPI_FLOAT, 0, 55, intercomm);
  printf("Processor %d data sent!\n", rank);

  MPI_Finalize();
}


I run the server program:

mpirun -np 2 app2
Processor 0 (7916, Receiver) initialized
Processor 1 (7918, Receiver) initialized
Opened port 0.1.0:2000
Waiting for connections on 0.1.0:2000...
Opened port 0.1.1:2001
Waiting for connections on 0.1.1:2001...


Then the client:

mpirun -np 1 app1 0.1.0:2000
Processor 0 (7933, Sender) initialized
Processor 0 connecting to '0.1.0:2000'
[alberto-giannettis-computer.local:07933] [0,1,0] ORTE_ERROR_LOG: Not  
found in file /tmp/buildpackage-3432/openmpi-1.2.4/orte/dss/ 
dss_unpack.c at line 209
[alberto-giannettis-computer.local:07933] [0,1,0] ORTE_ERROR_LOG: Not  
found in file /tmp/buildpackage-3432/openmpi-1.2.4/ompi/communicator/ 
comm_dyn.c at line 186
[alberto-giannettis-computer.local:07933] *** An error occurred in  
MPI_Comm_connect
[alberto-giannettis-computer.local:07933] *** on communicator  
MPI_COMM_SELF
[alberto-giannettis-computer.local:07933] *** MPI_ERR_INTERN:  
internal error
[alberto-giannettis-computer.local:07933] *** MPI_ERRORS_ARE_FATAL  
(goodbye)


Why do I have an internal error? If I try to connect to 0.1.1:2001  
from the client the program hangs.