On Feb 28, 2012, at 2:33 PM CST, Wei-keng Liao wrote: > How do I compare two MPI_Datatypes to see if they are equal? See this recent mpich-discuss@ thread: https://lists.mcs.anl.gov/mailman/htdig/mpich-discuss/2011-December/011442.html Feel free to revive this thread if that doesn't get you the information that you are looking for. -Dave