- remove a named semaphore
cc [ flag... ] file... -lrt [ library... ] #include <semaphore.h> int sem_unlink(const char *name);
The sem_unlink() function removes the semaphore named by the string name. If the semaphore named by name is currently referenced by other processes, then sem_unlink() has no effect on the state of the semaphore. If one or more processes have the semaphore open when sem_unlink() is called, destruction of the semaphore is postponed until all references to the semaphore have been destroyed by calls to sem_close(3RT), _Exit(2), or one of the exec functions (see exec(2)) . Calls to sem_open(3RT) to re-create or re-connect to the semaphore refer to a new semaphore after sem_unlink() is called. The sem_unlink() call does not block until all references have been destroyed; it returns immediately.
Upon successful completion, sem_unlink() returns 0. Otherwise, the semaphore is not changed and the function returns a value of -1 and sets errno to indicate the error.
The sem_unlink() function will fail if:
Permission is denied to unlink the named semaphore.
The length of name string exceeds PATH_MAX, or a pathname component is longer than NAME_MAX while _POSIX_NO_TRUNC is in effect.
The named semaphore does not exist.
The sem_unlink() function is not supported by the system.
See attributes(5) for descriptions of the following attributes:
Solaris 2.6 was the first release to support the Asynchronous Input and Output option. Prior to this release, this function always returned -1 and set errno to ENOSYS.