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+.. Permission is granted to copy, distribute and/or modify this
+.. document under the terms of the GNU Free Documentation License,
+.. Version 1.1 or any later version published by the Free Software
+.. Foundation, with no Invariant Sections, no Front-Cover Texts
+.. and no Back-Cover Texts. A copy of the license is included at
+.. Documentation/userspace-api/media/fdl-appendix.rst.
+..
+.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
+
+.. _VIDIOC_ENUMAUDIO:
+
+**********************
+ioctl VIDIOC_ENUMAUDIO
+**********************
+
+Name
+====
+
+VIDIOC_ENUMAUDIO - Enumerate audio inputs
+
+
+Synopsis
+========
+
+.. c:function:: int ioctl( int fd, VIDIOC_ENUMAUDIO, struct v4l2_audio *argp )
+ :name: VIDIOC_ENUMAUDIO
+
+
+Arguments
+=========
+
+``fd``
+ File descriptor returned by :ref:`open() <func-open>`.
+
+``argp``
+ Pointer to struct :c:type:`v4l2_audio`.
+
+
+Description
+===========
+
+To query the attributes of an audio input applications initialize the
+``index`` field and zero out the ``reserved`` array of a struct
+:c:type:`v4l2_audio` and call the :ref:`VIDIOC_ENUMAUDIO`
+ioctl with a pointer to this structure. Drivers fill the rest of the
+structure or return an ``EINVAL`` error code when the index is out of
+bounds. To enumerate all audio inputs applications shall begin at index
+zero, incrementing by one until the driver returns ``EINVAL``.
+
+See :ref:`VIDIOC_G_AUDIO <VIDIOC_G_AUDIO>` for a description of struct
+:c:type:`v4l2_audio`.
+
+
+Return Value
+============
+
+On success 0 is returned, on error -1 and the ``errno`` variable is set
+appropriately. The generic error codes are described at the
+:ref:`Generic Error Codes <gen-errors>` chapter.
+
+EINVAL
+ The number of the audio input is out of bounds.