| .. -*- coding: utf-8; mode: rst -*- | |
| .. _func-munmap: | |
| ************* | |
| V4L2 munmap() | |
| ************* | |
| Name | |
| ==== | |
| v4l2-munmap - Unmap device memory | |
| Synopsis | |
| ======== | |
| .. code-block:: c | |
| #include <unistd.h> | |
| #include <sys/mman.h> | |
| .. c:function:: int munmap( void *start, size_t length ) | |
| :name: v4l2-munmap | |
| Arguments | |
| ========= | |
| ``start`` | |
| Address of the mapped buffer as returned by the | |
| :ref:`mmap() <func-mmap>` function. | |
| ``length`` | |
| Length of the mapped buffer. This must be the same value as given to | |
| :ref:`mmap() <func-mmap>` and returned by the driver in the struct | |
| :c:type:`v4l2_buffer` ``length`` field for the | |
| single-planar API and in the struct | |
| :c:type:`v4l2_plane` ``length`` field for the | |
| multi-planar API. | |
| Description | |
| =========== | |
| Unmaps a previously with the :ref:`mmap() <func-mmap>` function mapped | |
| buffer and frees it, if possible. | |
| Return Value | |
| ============ | |
| On success :ref:`munmap() <func-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. |