POSIX Shared Memory

POSIX shared memory is actually a variation of mapped memory (see Creating and Using Mappings). The major differences are:

• You use shm_open() to open the shared memory object instead of calling open().

• You use shm_unlink() to close and delete the object instead of calling close() which does not remove the object.

The options in shm_open() substantially fewer than the number of options provided in open().