70 lines
1.3 KiB
ReStructuredText
70 lines
1.3 KiB
ReStructuredText
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.. -*- coding: utf-8; mode: rst -*-
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.. _media-func-open:
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************
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media open()
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************
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Name
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====
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media-open - Open a media device
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Synopsis
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========
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.. code-block:: c
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#include <fcntl.h>
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.. c:function:: int open( const char *device_name, int flags )
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:name: mc-open
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Arguments
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=========
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``device_name``
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Device to be opened.
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``flags``
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Open flags. Access mode must be either ``O_RDONLY`` or ``O_RDWR``.
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Other flags have no effect.
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Description
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===========
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To open a media device applications call :ref:`open() <media-func-open>` with the
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desired device name. The function has no side effects; the device
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configuration remain unchanged.
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When the device is opened in read-only mode, attempts to modify its
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configuration will result in an error, and ``errno`` will be set to
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EBADF.
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Return Value
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============
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:ref:`open() <func-open>` returns the new file descriptor on success. On error,
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-1 is returned, and ``errno`` is set appropriately. Possible error codes
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are:
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EACCES
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The requested access to the file is not allowed.
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EMFILE
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The process already has the maximum number of files open.
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ENFILE
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The system limit on the total number of open files has been reached.
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ENOMEM
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Insufficient kernel memory was available.
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ENXIO
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No device corresponding to this device special file exists.
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