Basic HTML version of Foils prepared 19 September 98

Foil 43 Hello World:C Example of Broadcast

From MPI Message Passing Interface Computational Science for Simulations -- Fall Semester 1998. by Geoffrey C. Fox, Nancy McCracken
#include "mpi.h"
main( int argc, char **argv )
{ char message[20];
  • int rank;
  • MPI_Init (&argc, &argv);
  • MPI_Comm_rank(MPI_COMM_WORLD, &rank); # Who is this processor
  • if( rank == 0 ) # We are on "root" -- Processor 0
    • strcpy(message,"Hello MPI World"); # Generate message
  • # MPI_Bcast sends from root=0 and receives on all other processor
  • MPI_Bcast(message,20, MPI_CHAR, 0, MPI_COMM_WORLD);
  • printf("This is a message from node %d saying %s\n", rank, message);
  • MPI_Finalize(); }
Note that all processes issue the broadcast operation, process 0 sends the message and all processes receive the message.

© Northeast Parallel Architectures Center, Syracuse University, npac@npac.syr.edu

If you have any comments about this server, send e-mail to webmaster@npac.syr.edu.

Page produced by wwwfoil on Sun Apr 11 1999