.. -*- coding: utf-8; mode: rst -*- .. _VIDIOC_G_STD: ************************************************************************** ioctl VIDIOC_G_STD, VIDIOC_S_STD, VIDIOC_SUBDEV_G_STD, VIDIOC_SUBDEV_S_STD ************************************************************************** Name ==== VIDIOC_G_STD - VIDIOC_S_STD - VIDIOC_SUBDEV_G_STD - VIDIOC_SUBDEV_S_STD - Query or select the video standard of the current input Synopsis ======== .. c:function:: int ioctl( int fd, VIDIOC_G_STD, v4l2_std_id *argp ) :name: VIDIOC_G_STD .. c:function:: int ioctl( int fd, VIDIOC_S_STD, const v4l2_std_id *argp ) :name: VIDIOC_S_STD .. c:function:: int ioctl( int fd, VIDIOC_SUBDEV_G_STD, v4l2_std_id *argp ) :name: VIDIOC_SUBDEV_G_STD .. c:function:: int ioctl( int fd, VIDIOC_SUBDEV_S_STD, const v4l2_std_id *argp ) :name: VIDIOC_SUBDEV_S_STD Arguments ========= ``fd`` File descriptor returned by :ref:`open() `. ``argp`` Pointer to :c:type:`v4l2_std_id`. Description =========== To query and select the current video standard applications use the :ref:`VIDIOC_G_STD ` and :ref:`VIDIOC_S_STD ` ioctls which take a pointer to a :ref:`v4l2_std_id ` type as argument. :ref:`VIDIOC_G_STD ` can return a single flag or a set of flags as in struct :c:type:`v4l2_standard` field ``id``. The flags must be unambiguous such that they appear in only one enumerated struct :c:type:`v4l2_standard` structure. :ref:`VIDIOC_S_STD ` accepts one or more flags, being a write-only ioctl it does not return the actual new standard as :ref:`VIDIOC_G_STD ` does. When no flags are given or the current input does not support the requested standard the driver returns an ``EINVAL`` error code. 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 :ref:`VIDIOC_ENUMINPUT` does not set the ``V4L2_IN_CAP_STD`` flag), then ``ENODATA`` error code is returned. Return Value ============ On success 0 is returned, on error -1 and the ``errno`` variable is set appropriately. The generic error codes are described at the :ref:`Generic Error Codes ` chapter. EINVAL The :ref:`VIDIOC_S_STD ` parameter was unsuitable. ENODATA Standard video timings are not supported for this input or output.