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author | Mauro Carvalho Chehab <mchehab@s-opensource.com> | 2016-09-08 12:21:01 +0300 |
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committer | Mauro Carvalho Chehab <mchehab@s-opensource.com> | 2016-09-09 15:56:33 +0300 |
commit | e452134cee5593612e515265247d271c36d6ca33 (patch) | |
tree | 6d1910e350b4b4ea1da806016f5f9f9ca689211b | |
parent | 9281f251bebe5618070e03041a7cdb81162b337d (diff) | |
download | linux-e452134cee5593612e515265247d271c36d6ca33.tar.xz |
[media] libv4l-introduction.rst: improve crossr-references
Use C cross-references to mention the V4L2 API calls on all
places it occurs inside this file.
While here, also mark constants as such.
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
-rw-r--r-- | Documentation/media/uapi/v4l/libv4l-introduction.rst | 33 |
1 files changed, 20 insertions, 13 deletions
diff --git a/Documentation/media/uapi/v4l/libv4l-introduction.rst b/Documentation/media/uapi/v4l/libv4l-introduction.rst index 1c1278d17fa7..ccc3c4d2fc0f 100644 --- a/Documentation/media/uapi/v4l/libv4l-introduction.rst +++ b/Documentation/media/uapi/v4l/libv4l-introduction.rst @@ -113,43 +113,47 @@ Libv4l device control functions The common file operation methods are provided by libv4l. -Those functions operate just like glibc -open/close/dup/ioctl/read/mmap/munmap: +Those functions operate just like the gcc function ``dup()`` and +V4L2 functions +:c:func:`open() <v4l2-open>`, :c:func:`close() <v4l2-close>`, +:c:func:`ioctl() <v4l2-ioctl>`, :c:func:`read() <v4l2-read>`, +:c:func:`mmap() <v4l2-mmap>` and :c:func:`munmap() <v4l2-munmap>`: .. c:function:: int v4l2_open(const char *file, int oflag, ...) - operates like the standard :ref:`open() <func-open>` function. + operates like the :c:func:`open() <v4l2-open>` function. .. c:function:: int v4l2_close(int fd) - operates like the standard :ref:`close() <func-close>` function. + operates like the :c:func:`close() <v4l2-close>` function. .. c:function:: int v4l2_dup(int fd) - operates like the standard dup() function, duplicating a file handler. + operates like the libc ``dup()`` function, duplicating a file handler. .. c:function:: int v4l2_ioctl (int fd, unsigned long int request, ...) - operates like the standard :ref:`ioctl() <func-ioctl>` function. + operates like the :c:func:`ioctl() <v4l2-ioctl>` function. .. c:function:: int v4l2_read (int fd, void* buffer, size_t n) - operates like the standard :ref:`read() <func-read>` function. + operates like the :c:func:`read() <v4l2-read>` function. .. c:function:: void v4l2_mmap(void *start, size_t length, int prot, int flags, int fd, int64_t offset); - operates like the standard :ref:`mmap() <func-mmap>` function. + operates like the :c:func:`munmap() <v4l2-munmap>` function. .. c:function:: int v4l2_munmap(void *_start, size_t length); - operates like the standard :ref:`munmap() <func-munmap>` function. + + operates like the :c:func:`munmap() <v4l2-munmap>` function. Those functions provide additional control: .. c:function:: int v4l2_fd_open(int fd, int v4l2_flags) opens an already opened fd for further use through v4l2lib and possibly - modify libv4l2's default behavior through the v4l2_flags argument. - Currently, v4l2_flags can be ``V4L2_DISABLE_CONVERSION``, to disable + modify libv4l2's default behavior through the ``v4l2_flags`` argument. + Currently, ``v4l2_flags`` can be ``V4L2_DISABLE_CONVERSION``, to disable format conversion. .. c:function:: int v4l2_set_control(int fd, int cid, int value) @@ -168,9 +172,12 @@ Those functions provide additional control: v4l1compat.so wrapper library ============================= -This library intercepts calls to open/close/ioctl/mmap/mmunmap +This library intercepts calls to +:c:func:`open() <v4l2-open>`, :c:func:`close() <v4l2-close>`, +:c:func:`ioctl() <v4l2-ioctl>`, :c:func:`mmap() <v4l2-mmap>` and +:c:func:`munmap() <v4l2-munmap>` operations and redirects them to the libv4l counterparts, by using -LD_PRELOAD=/usr/lib/v4l1compat.so. It also emulates V4L1 calls via V4L2 +``LD_PRELOAD=/usr/lib/v4l1compat.so``. It also emulates V4L1 calls via V4L2 API. It allows usage of binary legacy applications that still don't use |