удалить именованный семафор (remove a named semaphore)
Пролог (Prolog)
This manual page is part of the POSIX Programmer's Manual. The
Linux implementation of this interface may differ (consult the
corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
Имя (Name)
sem_unlink — remove a named semaphore
Синопсис (Synopsis)
#include <semaphore.h>
int sem_unlink(const char *name);
Описание (Description)
The sem_unlink() function shall remove the semaphore named by the
string name. If the semaphore named by name is currently
referenced by other processes, then sem_unlink() shall have 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(), _exit(),
or exec. Calls to sem_open() to recreate or reconnect to the
semaphore refer to a new semaphore after sem_unlink() is called.
The sem_unlink() call shall not block until all references have
been destroyed; it shall return immediately.
Возвращаемое значение (Return value)
Upon successful completion, the sem_unlink() function shall
return a value of 0. Otherwise, the semaphore shall not be
changed and the function shall return a value of -1 and set errno
to indicate the error.
Ошибки (Error)
The sem_unlink() function shall fail if:
EACCES
Permission is denied to unlink the named semaphore.
ENOENT
The named semaphore does not exist.
The sem_unlink() function may fail if:
ENAMETOOLONG
The length of the name argument exceeds {_POSIX_PATH_MAX}
on systems that do not support the XSI option or exceeds
{_XOPEN_PATH_MAX} on XSI systems, or has a pathname
component that is longer than {_POSIX_NAME_MAX} on systems
that do not support the XSI option or longer than
{_XOPEN_NAME_MAX} on XSI systems. A call to sem_unlink()
with a name argument that contains the same semaphore name
as was previously used in a successful sem_open() call
shall not give an [ENAMETOOLONG]
error.
The following sections are informative.
Примеры (Examples)
None.
Использование в приложениях (Application usage)
None.
Обоснование (Rationale)
None.
Будущие направления (Future directions)
A future version might require the sem_open() and sem_unlink()
functions to have semantics similar to normal file system
operations.
Смотри также (See also)
semctl(3p), semget(3p), semop(3p), sem_close(3p), sem_open(3p)
The Base Definitions volume of POSIX.1‐2017, semaphore.h(0p)