ioctl VIDIOC_G_OUTPUT, VIDIOC_S_OUTPUT

&manvol;

VIDIOC_G_OUTPUT

VIDIOC_S_OUTPUT

Query or select the current video output

    	int ioctl
    	int fd
    	int request
    	int *argp

## Arguments

`fd`

- &fd;

`request`

- VIDIOC_G_OUTPUT, VIDIOC_S_OUTPUT

`argp`

## Description

To query the current video output applications call the `VIDIOC_G_OUTPUT` ioctl with a pointer to an integer where the driver stores the number of the output, as in the &v4l2-output; index field. This ioctl will fail only when there are no video outputs, returning the &EINVAL;.

To select a video output applications store the number of the desired output in an integer and call the `VIDIOC_S_OUTPUT` ioctl with a pointer to this integer. Side effects are possible. For example outputs may support different video standards, so the driver may implicitly switch the current standard. It is good practice to select an output before querying or negotiating any other parameters.

Information about video outputs is available using the &VIDIOC-ENUMOUTPUT; ioctl.

&return-value;

EINVAL

- The number of the video output is out of bounds, or there are no video outputs at all.