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1.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later2.. c:namespace:: V4L3 4.. _VIDIOC_LOG_STATUS:5 6***********************7ioctl VIDIOC_LOG_STATUS8***********************9 10Name11====12 13VIDIOC_LOG_STATUS - Log driver status information14 15Synopsis16========17 18.. c:macro:: VIDIOC_LOG_STATUS19 20``int ioctl(int fd, VIDIOC_LOG_STATUS)``21 22Arguments23=========24 25``fd``26 File descriptor returned by :c:func:`open()`.27 28Description29===========30 31As the video/audio devices become more complicated it becomes harder to32debug problems. When this ioctl is called the driver will output the33current device status to the kernel log. This is particular useful when34dealing with problems like no sound, no video and incorrectly tuned35channels. Also many modern devices autodetect video and audio standards36and this ioctl will report what the device thinks what the standard is.37Mismatches may give an indication where the problem is.38 39This ioctl is optional and not all drivers support it. It was introduced40in Linux 2.6.15.41 42Return Value43============44 45On success 0 is returned, on error -1 and the ``errno`` variable is set46appropriately. The generic error codes are described at the47:ref:`Generic Error Codes <gen-errors>` chapter.48