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+.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
+.. c:namespace:: V4L
+
+.. _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:macro:: VIDIOC_G_STD
+
+``int ioctl(int fd, VIDIOC_G_STD, v4l2_std_id *argp)``
+
+.. c:macro:: VIDIOC_S_STD
+
+``int ioctl(int fd, VIDIOC_S_STD, const v4l2_std_id *argp)``
+
+.. c:macro:: VIDIOC_SUBDEV_G_STD
+
+``int ioctl(int fd, VIDIOC_SUBDEV_G_STD, v4l2_std_id *argp)``
+
+.. c:macro:: VIDIOC_SUBDEV_S_STD
+
+``int ioctl(int fd, VIDIOC_SUBDEV_S_STD, const v4l2_std_id *argp)``
+
+Arguments
+=========
+
+``fd``
+ File descriptor returned by :c:func:`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 <VIDIOC_G_STD>` and :ref:`VIDIOC_S_STD <VIDIOC_G_STD>` ioctls which take a pointer to a
+:ref:`v4l2_std_id <v4l2-std-id>` type as argument. :ref:`VIDIOC_G_STD <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 <VIDIOC_G_STD>` accepts one or more flags, being a write-only ioctl it
+does not return the actual new standard as :ref:`VIDIOC_G_STD <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.
+
+Calling ``VIDIOC_SUBDEV_S_STD`` on a subdev device node that has been registered
+in read-only mode is not allowed. An error is returned and the errno variable is
+set to ``-EPERM``.
+
+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 <gen-errors>` chapter.
+
+EINVAL
+ The :ref:`VIDIOC_S_STD <VIDIOC_G_STD>` parameter was unsuitable.
+
+ENODATA
+ Standard video timings are not supported for this input or output.
+
+EPERM
+ ``VIDIOC_SUBDEV_S_STD`` has been called on a read-only subdevice.