Process waits for message. Process receives message. Signal unblocks process. Target process receives signal message. Process waits on death of child.
Child dies or signal unblocks process.
Parent waits on death, terminates itself or has already terminated. Process symbolic names QNX encourages the development of applications that are split up into cooperating processes. An application that exists as a team of cooperating processes exhibits greater concurrency and can be network-distributed for greater performance. Splitting up applications into cooperating processes requires special considerations, however. For example, let's say you have a database server process that provides services to an arbitrary number of clients.