I am trying to understand the behavior of firstmessage.c when I change the count variable in MPI_sSend and MPI_Recv commands. When I change it from 6 to 5 in MPI_Ssend (or in both Ssend and Recv), I get the following output:
1: Got message <Hello Hello>
0: Sent message <Hello>
But if I make the same change for MPI_Recv, the result is:1: Got message <>
Could you please explain it?