1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later 2 3.. _VIDIOC_LOG_STATUS: 4 5*********************** 6ioctl VIDIOC_LOG_STATUS 7*********************** 8 9Name 10==== 11 12VIDIOC_LOG_STATUS - Log driver status information 13 14 15Synopsis 16======== 17 18.. c:function:: int ioctl( int fd, VIDIOC_LOG_STATUS) 19 :name: VIDIOC_LOG_STATUS 20 21 22Arguments 23========= 24 25``fd`` 26 File descriptor returned by :ref:`open() <func-open>`. 27 28 29Description 30=========== 31 32As the video/audio devices become more complicated it becomes harder to 33debug problems. When this ioctl is called the driver will output the 34current device status to the kernel log. This is particular useful when 35dealing with problems like no sound, no video and incorrectly tuned 36channels. Also many modern devices autodetect video and audio standards 37and this ioctl will report what the device thinks what the standard is. 38Mismatches may give an indication where the problem is. 39 40This ioctl is optional and not all drivers support it. It was introduced 41in Linux 2.6.15. 42 43 44Return Value 45============ 46 47On success 0 is returned, on error -1 and the ``errno`` variable is set 48appropriately. The generic error codes are described at the 49:ref:`Generic Error Codes <gen-errors>` chapter. 50