Shared Memory

Unix supports sharing memory between processes. Normally read-only shared memory (such as that containing executables and shared libraries) is shared automatically by the operating system.

A program may also use read-write shared memory, to pass data between processes. Accesses to such memory should be synchronized between the processes, using some locking mechanism.

Hard-To-Find memory corruptions could result from use of such shared memory - a process could crash because of accessing data in a shared region, that was corrupted by a completely different process (that might even no longer be running).