66 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			ReStructuredText
		
	
	
	
	
	
			
		
		
	
	
			66 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			ReStructuredText
		
	
	
	
	
	
| .. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
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| .. c:namespace:: MC
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| 
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| .. _media-func-open:
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| 
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| ************
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| media open()
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| ************
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| 
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| Name
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| ====
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| 
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| media-open - Open a media device
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| 
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| Synopsis
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| ========
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| 
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| .. code-block:: c
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| 
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|     #include <fcntl.h>
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| 
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| .. c:function:: int open( const char *device_name, int flags )
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| 
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| Arguments
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| =========
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| 
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| ``device_name``
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|     Device to be opened.
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| 
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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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| 
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| Description
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| ===========
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| 
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| To open a media device applications call :c: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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| 
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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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| 
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| Return Value
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| ============
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| 
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| :c: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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| 
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| EACCES
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|     The requested access to the file is not allowed.
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| 
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| EMFILE
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|     The process already has the maximum number of files open.
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| 
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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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| 
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| ENOMEM
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|     Insufficient kernel memory was available.
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| 
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| ENXIO
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|     No device corresponding to this device special file exists.
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