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.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
.. c:namespace:: DTV.audio

.. _audio_fopen:

=======================
Digital TV audio open()
=======================

Name
----

Digital TV audio open()

.. attention:: This ioctl is deprecated

Synopsis
--------

.. c:function:: int open(const char *deviceName, int flags)

Arguments
---------

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    -  .. row 1

       -  const char \*deviceName

       -  Name of specific audio device.

    -  .. row 2

       -  int flags

       -  A bit-wise OR of the following flags:

    -  .. row 3

       -
       -  O_RDONLY read-only access

    -  .. row 4

       -
       -  O_RDWR read/write access

    -  .. row 5

       -
       -  O_NONBLOCK open in non-blocking mode

    -  .. row 6

       -
       -  (blocking mode is the default)

Description
-----------

This system call opens a named audio device (e.g.
/dev/dvb/adapter0/audio0) for subsequent use. When an open() call has
succeeded, the device will be ready for use. The significance of
blocking or non-blocking mode is described in the documentation for
functions where there is a difference. It does not affect the semantics
of the open() call itself. A device opened in blocking mode can later be
put into non-blocking mode (and vice versa) using the F_SETFL command
of the fcntl system call. This is a standard system call, documented in
the Linux manual page for fcntl. Only one user can open the Audio Device
in O_RDWR mode. All other attempts to open the device in this mode will
fail, and an error code will be returned. If the Audio Device is opened
in O_RDONLY mode, the only ioctl call that can be used is
AUDIO_GET_STATUS. All other call will return with an error code.

Return Value
------------

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    -  .. row 1

       -  ``ENODEV``

       -  Device driver not loaded/available.

    -  .. row 2

       -  ``EBUSY``

       -  Device or resource busy.

    -  .. row 3

       -  ``EINVAL``

       -  Invalid argument.