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   shmdt.3p    ( 3 )

операция отсоединения разделяемой памяти XSI (XSI shared memory detach operation)

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)

shmdt — XSI shared memory detach operation

Синопсис (Synopsis)

#include <sys/shm.h>

int shmdt(const void *shmaddr);


Описание (Description)

The shmdt() function operates on XSI shared memory (see the Base
       Definitions volume of POSIX.1‐2017, Section 3.346, Shared Memory
       Object).  It is unspecified whether this function interoperates
       with the realtime interprocess communication facilities defined
       in Section 2.8, Realtime.

The shmdt() function detaches the shared memory segment located at the address specified by shmaddr from the address space of the calling process.


Возвращаемое значение (Return value)

Upon successful completion, shmdt() shall decrement the value of
       shm_nattch in the data structure associated with the shared
       memory ID of the attached shared memory segment and return 0.
       Also, the shm_dtime timestamp shall be set to the current time,
       as described in Section 2.7.1, IPC General Description.

Otherwise, the shared memory segment shall not be detached, shmdt() shall return -1, and errno shall be set to indicate the error.


Ошибки (Error)

The shmdt() function shall fail if:

EINVAL The value of shmaddr is not the data segment start address of a shared memory segment.

The following sections are informative.


Примеры (Examples)

None.

Использование в приложениях (Application usage)

The POSIX Realtime Extension defines alternative interfaces for
       interprocess communication. Application developers who need to
       use IPC should design their applications so that modules using
       the IPC routines described in Section 2.7, XSI Interprocess
       Communication can be easily modified to use the alternative
       interfaces.

Обоснование (Rationale)

None.

Будущие направления (Future directions)

None.

Смотри также (See also)

Section 2.7, XSI Interprocess Communication, Section 2.8,
       Realtime, exec(1p), exit(3p), fork(3p), shmat(3p), shmctl(3p),
       shmget(3p), shm_open(3p), shm_unlink(3p)

The Base Definitions volume of POSIX.1‐2017, Section 3.346, Shared Memory Object, sys_shm.h(0p)