OpenCloudOS-Kernel/Documentation/userspace-api/media/dvb/audio-fopen.rst

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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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- const char \*deviceName
- Name of specific audio device.
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- int flags
- A bit-wise OR of the following flags:
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-
- O_RDONLY read-only access
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-
- O_RDWR read/write access
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-
- O_NONBLOCK open in non-blocking mode
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-
- (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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- ``ENODEV``
- Device driver not loaded/available.
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- ``EBUSY``
- Device or resource busy.
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- ``EINVAL``
- Invalid argument.