1.. Permission is granted to copy, distribute and/or modify this 2.. document under the terms of the GNU Free Documentation License, 3.. Version 1.1 or any later version published by the Free Software 4.. Foundation, with no Invariant Sections, no Front-Cover Texts 5.. and no Back-Cover Texts. A copy of the license is included at 6.. Documentation/userspace-api/media/fdl-appendix.rst. 7.. 8.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections 9 10.. _dmx-munmap: 11 12************ 13DVB munmap() 14************ 15 16Name 17==== 18 19dmx-munmap - Unmap device memory 20 21.. warning:: This API is still experimental. 22 23 24Synopsis 25======== 26 27.. code-block:: c 28 29 #include <unistd.h> 30 #include <sys/mman.h> 31 32 33.. c:function:: int munmap( void *start, size_t length ) 34 :name: dmx-munmap 35 36Arguments 37========= 38 39``start`` 40 Address of the mapped buffer as returned by the 41 :ref:`mmap() <dmx-mmap>` function. 42 43``length`` 44 Length of the mapped buffer. This must be the same value as given to 45 :ref:`mmap() <dmx-mmap>`. 46 47 48Description 49=========== 50 51Unmaps a previously with the :ref:`mmap() <dmx-mmap>` function mapped 52buffer and frees it, if possible. 53 54 55Return Value 56============ 57 58On success :ref:`munmap() <dmx-munmap>` returns 0, on failure -1 and the 59``errno`` variable is set appropriately: 60 61EINVAL 62 The ``start`` or ``length`` is incorrect, or no buffers have been 63 mapped yet. 64