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+.. -*- coding: utf-8; mode: rst -*-
+
+.. _VIDIOC_G_STD:
+
+********************************
+ioctl VIDIOC_G_STD, VIDIOC_S_STD
+********************************
+
+Name
+====
+
+VIDIOC_G_STD - VIDIOC_S_STD - Query or select the video standard of the current input
+
+
+Synopsis
+========
+
+.. cpp:function:: int ioctl( int fd, int request, v4l2_std_id *argp )
+
+.. cpp:function:: int ioctl( int fd, int request, const v4l2_std_id *argp )
+
+
+Arguments
+=========
+
+``fd``
+ File descriptor returned by :ref:`open() <func-open>`.
+
+``request``
+ VIDIOC_G_STD, VIDIOC_S_STD
+
+``argp``
+
+
+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
+:ref:`v4l2_standard <v4l2-standard>` field ``id``. The flags must be
+unambiguous such that they appear in only one enumerated
+:ref:`struct v4l2_standard <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.
+
+
+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.