Originální popis anglicky:
shm_unlink - remove a shared memory object (
REALTIME)
Návod, kniha: POSIX Programmer's Manual
#include <sys/mman.h>
int shm_unlink(const char *
name);
The
shm_unlink() function shall remove the name of the shared memory
object named by the string pointed to by
name.
If one or more references to the shared memory object exist when the object is
unlinked, the name shall be removed before
shm_unlink() returns, but
the removal of the memory object contents shall be postponed until all open
and map references to the shared memory object have been removed.
Even if the object continues to exist after the last
shm_unlink(), reuse
of the name shall subsequently cause
shm_open() to behave as if no
shared memory object of this name exists (that is,
shm_open() will fail
if O_CREAT is not set, or will create a new shared memory object if O_CREAT is
set).
Upon successful completion, a value of zero shall be returned. Otherwise, a
value of -1 shall be returned and
errno set to indicate the error. If
-1 is returned, the named shared memory object shall not be changed by this
function call.
The
shm_unlink() function shall fail if:
- EACCES
- Permission is denied to unlink the named shared memory
object.
- ENAMETOOLONG
- The length of the name argument exceeds {PATH_MAX}
or a pathname component is longer than {NAME_MAX}.
- ENOENT
- The named shared memory object does not exist.
The following sections are informative.
None.
Names of memory objects that were allocated with
open() are deleted with
unlink() in the usual fashion. Names of memory objects that were
allocated with
shm_open() are deleted with
shm_unlink(). Note
that the actual memory object is not destroyed until the last close and unmap
on it have occurred if it was already in use.
None.
None.
close() ,
mmap() ,
munmap() ,
shmat() ,
shmctl() ,
shmdt() ,
shm_open() , the Base Definitions
volume of IEEE Std 1003.1-2001,
<sys/mman.h>
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable
Operating System Interface (POSIX), The Open Group Base Specifications Issue
6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. In the event of any discrepancy between
this version and the original IEEE and The Open Group Standard, the original
IEEE and The Open Group Standard is the referee document. The original
Standard can be obtained online at http://www.opengroup.org/unix/online.html
.
