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35 .Nd initialize an unnamed semaphore
41 .Fn sem_init "sem_t *sem" "int pshared" "unsigned int value"
45 function initializes the unnamed semaphore pointed to by
52 specifies a shared semaphore that can be used by multiple processes,
53 the semaphore should be located in shared memory region (see
58 any process having read and write access to address
60 can perform semaphore operations on
63 Following a successful call to
66 can be used as an argument in subsequent calls to
74 argument is no longer valid after a successful call to
81 function will fail if:
89 Memory allocation error.