Operating Systems: Concurrent and Distributed Software Design

9.5. Requirements for process interaction

Bearing these structural points on process placement in mind we now look in more detail at why processes might need to interact and how their interactions might be supported in a system.

1. Processes may need to cooperate to carry out some task

   Specifically, one process may need to make a request for service of some other process and eventually may wait for the service to be done. An example from Section 9.1 is a request from a process in the file management module to a disk-handler process to read the disk and to wait for the required data to be available in memory before proceeding.

   We have already seen in Section 3.2 that the disk-handler process synchronizes with the disk in a similar way. It issues the ...