ioctl VIDIOC_G_STD, VIDIOC_S_STD &manvol; VIDIOC_G_STD VIDIOC_S_STD Query or select the video standard of the current input int ioctl int fd int request v4l2_std_id *argp int ioctl int fd int request const v4l2_std_id *argp fd &fd; request VIDIOC_G_STD, VIDIOC_S_STD argp To query and select the current video standard applications use the VIDIOC_G_STD and VIDIOC_S_STD ioctls which take a pointer to a &v4l2-std-id; type as argument. VIDIOC_G_STD can return a single flag or a set of flags as in &v4l2-standard; field id. The flags must be unambiguous such that they appear in only one enumerated v4l2_standard structure. VIDIOC_S_STD accepts one or more flags, being a write-only ioctl it does not return the actual new standard as VIDIOC_G_STD does. When no flags are given or the current input does not support the requested standard the driver returns an &EINVAL;. When the standard set is ambiguous drivers may return EINVAL or choose any of the requested standards. If the current input or output does not support standard video timings (e.g. if &VIDIOC-ENUMINPUT; does not set the V4L2_IN_CAP_STD flag), then &ENODATA; is returned. &return-value; EINVAL The VIDIOC_S_STD parameter was unsuitable. ENODATA Standard video timings are not supported for this input or output.