Hello. I have problems in getting a shared memory to work. What works is my shmalloc() which is used for sharing memory over fork(). What does not work is sharing memory between arbitrary processes. This latter uses ftok() with a pathname (e.g., "/tmp/globalshm") in identifying the shared memory. Each process uses the pathname for gaining access to the shared memory. The simple example in "http://www.funet.fi/~kouhia/shmserver.tar.gz" does not work. It looks like shmserver creates the shared memory, but shmclient cannot find it. I use now shmget() but I have also used mmap() for shared memory. I don't remember the reason why I moved from mmap() to shmget(). Were there any limitations? What then is the "/dev/shm" seen in the "df" listing? How that is used? Best regards, Juhana