projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 5377d91f MH |
1 | .. -*- coding: utf-8; mode: rst -*- |
| 2 | ||
| af4a4d0d | 3 | .. _VIDIOC_LOG_STATUS: |
| 5377d91f MH |
4 | |
| 5 | *********************** | |
| 6 | ioctl VIDIOC_LOG_STATUS | |
| 7 | *********************** | |
| 8 | ||
| 15e7d615 | 9 | Name |
| 586027ce | 10 | ==== |
| 5377d91f | 11 | |
| 586027ce | 12 | VIDIOC_LOG_STATUS - Log driver status information |
| 5377d91f | 13 | |
| 15e7d615 MCC |
14 | |
| 15 | Synopsis | |
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16 | ======== |
| 17 | ||
| b7e67f6c | 18 | .. cpp:function:: int ioctl( int fd, int request ) |
| 5377d91f | 19 | |
| 586027ce | 20 | |
| 15e7d615 | 21 | Arguments |
| 586027ce MCC |
22 | ========= |
| 23 | ||
| 24 | ||
| 25 | ||
| 15e7d615 | 26 | Description |
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27 | =========== |
| 28 | ||
| 29 | As the video/audio devices become more complicated it becomes harder to | |
| 30 | debug problems. When this ioctl is called the driver will output the | |
| 31 | current device status to the kernel log. This is particular useful when | |
| 32 | dealing with problems like no sound, no video and incorrectly tuned | |
| 33 | channels. Also many modern devices autodetect video and audio standards | |
| 34 | and this ioctl will report what the device thinks what the standard is. | |
| 35 | Mismatches may give an indication where the problem is. | |
| 36 | ||
| 37 | This ioctl is optional and not all drivers support it. It was introduced | |
| 38 | in Linux 2.6.15. | |
| 39 | ||
| 40 | ||
| 15e7d615 | 41 | Return Value |
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42 | ============ |
| 43 | ||
| 44 | On success 0 is returned, on error -1 and the ``errno`` variable is set | |
| 45 | appropriately. The generic error codes are described at the | |
| 46 | :ref:`Generic Error Codes <gen-errors>` chapter. |