Hi, I've just installed Mpich2 (using 3.0.4 sources) on my computer and every thing works fine. Now, I have to work on MPI_Comm_spawn and I have some difficulties. I've found a nice example that is provided with Mpich2 sources in Mpich2/share/examples/logging This example is based on 2 files : comm2_spawn_parent.c and comm2_spawn_child.c. I've compiled these two files but I have an error when I try to run this test : $ mpiexec -np 2 ./comm2_spawn_parent [proxy:1:0@bambou] HYDU_create_process (./utils/launch/launch.c:75): execvp error on file comm2_spawn_child (No such file or directory) However, "comm2_spawn_child" is present in the current directory. Thus I've tried to use a "-path" option but it's not recognized : $mpiexec -path mypath -np 2 ./comm2_spawn_parent match_arg (./utils/args/args.c:160): unrecognized argument path I've looked for some documentation of this test but I haven't found anything. Regards, Anne-Sophie