kernel_samsung_a34x-permissive/Documentation/media/uapi/dvb/dmx-munmap.rst

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.. _dmx-munmap:
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DVB munmap()
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Name
====
dmx-munmap - Unmap device memory
.. warning:: This API is still experimental.
Synopsis
========
.. code-block:: c
#include <unistd.h>
#include <sys/mman.h>
.. c:function:: int munmap( void *start, size_t length )
:name: dmx-munmap
Arguments
=========
``start``
Address of the mapped buffer as returned by the
:ref:`mmap() <dmx-mmap>` function.
``length``
Length of the mapped buffer. This must be the same value as given to
:ref:`mmap() <dmx-mmap>`.
Description
===========
Unmaps a previously with the :ref:`mmap() <dmx-mmap>` function mapped
buffer and frees it, if possible.
Return Value
============
On success :ref:`munmap() <dmx-munmap>` returns 0, on failure -1 and the
``errno`` variable is set appropriately:
EINVAL
The ``start`` or ``length`` is incorrect, or no buffers have been
mapped yet.