.\"	$Darwin$
.\"
.\" Wilfredo Sanchez, wsanchez@apple.com
.\" Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
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.Dd September 20, 1999
.Dt SHM_UNLINK 2
.Os Darwin
.Sh NAME
.Nm shm_unlink
.Nd remove shared memory object
.Sh SYNOPSIS
.Fd #include <sys/mman.h>
.Ft int
.Fn shm_unlink "const char *name"
.Sh DESCRIPTION
The
.Fn shm_unlink
function removes the shared memory object named by
.Fa name .
If no process has the file open, then all resources associated
with the object are reclaimed.
If one or more process have the object open, the name removed,
but the removal of the memory object is delayed until all
references to it have been closed.
.Sh RETURN VALUES
Upon successful completion, a value of 0 is returned.
Otherwise, a value of -1 is returned and
.Va errno
is set to indicate the error, and the named shared memory object
will remain unchanged.
.Sh ERRORS
The
.Fn shm_unlink
succeeds unless:
.Bl -tag -width Er
.It Bq Er EACCES
Permission is denied to be remove the object.
.It Bq Er ENAMETOOLONG
.Fa name
exceeded
.Dv SHM_NAME_MAX
characters.
.It Bq Er ENOENT
The named object does not exist.
.El
.Sh SEE ALSO
.Xr close 2 ,
.Xr mmap 2 ,
.Xr munmap 2 ,
.Xr shmat 2 ,
.Xr shmctl 2 ,
.Xr shm_open 2
.Sh HISTORY
.Fn shm_open
is specified in the POSIX Realtime Extension (1003.1b-1993/1003.1i-1995).