I was thinking more about what mmap has to do with anything. Anyway it depends on the API you use. libc read/write are thread safe for instance. Obviously you s

I was thinking more about what mmap has to do with anything. Anyway it depends on the API you use. libc read/write are thread safe for instance. Obviously you still have to synchronize the higher level concept of writes if you are not writing an object all at once, but this is rather trivial to do.