This section describes the constants used by the synchronization interfaces:
The pthread_mutexattr_t structure and the functions which set the mattr_kind field use the following flags to specify the type of mutex.
The various POSIX synchronization primitives (mutexes, reader-writer locks, and condition variables) use the following flags to indicate whether the primitive is private to a single process or if it can be shared with other processes.
POSIX mutex interfaces use the following flags to set and get the value of the protocol attribute.