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SHM_UNLINK(2)               BSD System Calls Manual              SHM_UNLINK(2)

NAME
     shm_unlink -- remove shared memory object

SYNOPSIS
     #include <sys/mman.h>

     int
     shm_unlink(const char *name);

DESCRIPTION
     The shm_unlink() function disassociates the shared memory object specified by name from that name.  The
     resources associated with the shared memory object remain intact until the last file descriptor refer-ence reference
     ence is removed, e.g., by close(2) or munmap(2), at which point the resources are reclaimed (if no ref-erences references
     erences exist at the time of the call to shm_unlink(), the resources are reclaimed immediately).  The
     name can only be reused when it is bound to a new shared memory object with a call to shm_open(2) with
     the O_CREAT flag.

RETURN VALUES
     Upon successful completion, a value of 0 is returned.  Otherwise, a value of -1 is returned and errno
     is set to indicate the error, and the named shared memory object will remain unchanged.

ERRORS
     The shm_unlink() succeeds unless:

     [EACCES]           Permission is denied to be remove the object.

     [ENAMETOOLONG]     name exceeded the name size limit.  This is currently PSHMNAMLEN characters (defined
                        in <sys/posix_shm.h>), but this may change in the future.

     [ENOENT]           The named object does not exist.

SEE ALSO
     close(2), mmap(2), munmap(2), shm_open(2), shmat(2), shmctl(2)

HISTORY
     shm_open() is specified in the POSIX Realtime Extension (1003.1b-1993/1003.1i-1995).

Darwin                          August 31, 2006                         Darwin

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