>Anyway. What I wanted to ask you all is this - does anyone know of >MAP_COPY or MAP_PRIVATE being used in real software? I can write >cases for them, but it is more work and I thought that I would ask >and see if anyone knows of people actually using them. It somewhat >complicates things (and they are slower than their more public >compatriots). I always saw mmap as private, until it was specifically shared, in which case you are correct about keeping all changes in real-time. As far as MAP_COPY, the only big usage that comes to mind is POSIX and fork(). But even elsewhere, technically, there could be many cases where you pass a buffer to another app, and use MAP_COPY rather than specifically making a copy yourself. Just an idea. Rudyatek