Interprocess Communication (IPC)

[ ] Mechanism for processes to communicate and to synchronize their actions.

[ ] Message system – processes communicate with each other without resorting to shared variables.

[ ] IPC facility provides two operations:

* send(message) –message size fixed or variable
* receive(message)

[ ] If P and Q wish to communicate, they need to:

* establish a communication link between them
* exchange messages via send/receive

[ ] Implementation of communication link

* physical (e.g., shared memory, hardware bus) considered later
* logical (e.g., logical properties) now