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semaphore(3head) [sunos man page]

semaphore.h(3HEAD)						      Headers							semaphore.h(3HEAD)

semaphore.h, semaphore - semaphores SYNOPSIS
#include <semaphore.h> DESCRIPTION
The <semaphore.h> header defines the sem_t type, used in performing semaphore operations. The semaphore can be implemented using a file descriptor, in which case applications are able to open up at least a total of {OPEN_MAX} files and semaphores. The symbol SEM_FAILED is defined (see sem_open(3RT)). Inclusion of the <semaphore.h> header can make visible symbols defined in the headers <fcntl.h> and <sys/types.h>. See fcntl.h(3HEAD) and types.h(3HEAD). ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ SEE ALSO
fcntl.h(3HEAD), types.h(3HEAD), sem_destroy(3RT), sem_getvalue(3RT), sem_init(3RT), sem_open(3RT), sem_post(3RT), sem_timedwait(3RT), sem_unlink(3RT), sem_wait(3RT), attributes(5), standards(5) SunOS 5.10 10 Sep 2004 semaphore.h(3HEAD)

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sem_unlink(3RT) 					    Realtime Library Functions						   sem_unlink(3RT)

sem_unlink - remove a named semaphore SYNOPSIS
cc [ flag... ] file... -lrt [ library... ] #include <semaphore.h> int sem_unlink(const char *name); DESCRIPTION
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. RETURN VALUES
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. ERRORS
The sem_unlink() function will fail if: EACCES Permission is denied to unlink the named semaphore. ENAMETOOLONG The length of name string exceeds PATH_MAX, or a pathname component is longer than NAME_MAX while _POSIX_NO_TRUNC is in effect. ENOENT The named semaphore does not exist. ENOSYS The sem_unlink() function is not supported by the system. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ |MT-Level |MT-Safe | +-----------------------------+-----------------------------+ SEE ALSO
exec(2), exit(2), sem_close(3RT), sem_open(3RT), attributes(5), standards(5) NOTES
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. SunOS 5.10 28 Jun 2002 sem_unlink(3RT)

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