I was wondering if it is possible to have the shared memory mmap'ed file be in a different location other than /dev/shm or /tmp.  Is there an environment variable I can specify?  

I am using MPICH2 and have configured it like this:

./configure --prefix=/opt/mpich2 --with-device=ch3:nemesis --with-shared-memory=mmap --enable-nemesis-shm-collectives

Is this configuration sufficient for MPICH2 to use the shared memory file?

thanks very much,

    -Dustin