> Maybe the exact behavior varies by platform. Yes, that was the case. Also I probably confused SO_REUSEADDR, which in Windows is implemented quite differently

> Maybe the exact behavior varies by platform. Yes, that was the case. Also I probably confused SO_REUSEADDR, which in Windows is implemented quite differently, with SO_REUSEPORT. Anyway, I can confirm that on Windows (2000) I could open N programs whose receiving socket was bound on the same address:port and all of them would receive a copy of the transmitted datagram. If say I run 5 copies of the same agent, all of them would display the same data. Those were stand alone applications without any shared memory, so apparently the system made a copy of the buffer for each socket. I'm not sure however if I tested this particular behavior also under Unix, since I needed it only on the graphical interface, but on Windows it definitely worked.