dmx-munmap.rst

 1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
 2.. c:namespace:: DTV.dmx
 3
 4.. _dmx-munmap:
 5
 6************
 7DVB munmap()
 8************
 9
10Name
11====
12
13dmx-munmap - Unmap device memory
14
15.. warning:: This API is still experimental.
16
17Synopsis
18========
19
20.. code-block:: c
21
22    #include <unistd.h>
23    #include <sys/mman.h>
24
25.. c:function:: int munmap( void *start, size_t length )
26
27Arguments
28=========
29
30``start``
31    Address of the mapped buffer as returned by the
32    :c:func:`mmap()` function.
33
34``length``
35    Length of the mapped buffer. This must be the same value as given to
36    :c:func:`mmap()`.
37
38Description
39===========
40
41Unmaps a previously with the :c:func:`mmap()` function mapped
42buffer and frees it, if possible.
43
44Return Value
45============
46
47On success :c:func:`munmap()` returns 0, on failure -1 and the
48``errno`` variable is set appropriately:
49
50EINVAL
51    The ``start`` or ``length`` is incorrect, or no buffers have been
52    mapped yet.