PPT Slide
IPC in Mach
- Interesting IPC structure that has influenced OS design.
- Mach task = traditional process (at least one thread plus memory objects, etc.).
- Mach port = message queue variation:
- Only one task can receive messages on a port, but any task can send a message to a port.
- Children can inherit ports.
- Messages are sent down ports. Messages can be either:
- Data
- Out-of-line data - pass part of the sender’s address space to the receiver.
- Ports - can pass port addresses back and forth.