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XOPENDEVICE(3)							  XOPENDEVICE(3)

NAME
     XOpenDevice, XCloseDevice - open or close an extension input device

SYNOPSIS
     #include <X11/extensions/XInput.h>

     XDevice *XOpenDevice( Display *display,
			   XID device_id);

     XCloseDevice( Display *display,
		   XDevice *device);

     display
	    Specifies the connection to the X server.

     device_id
	    Specifies the id of the device to be opened

     device
	    Specifies the device to be closed

DESCRIPTION
	 The XOpenDevice request makes an input device accessible to a
	 client through input extension protocol requests. If
	 successful, it returns a pointer to an XDevice structure.

	 The XCloseDevice request makes an input device inaccessible to
	 a client through input extension protocol requests. Before
	 terminating, and client that has opened input devices through
	 the input extension should close them via CloseDevice.

	 When a client makes an XCloseDevice request, any active grabs
	 that the client has on the device are released. Any event
	 selections that the client has are deleted, as well as any
	 passive grabs. If the requesting client is the last client
	 accessing the device, the server may disable all access by X to
	 the device.

	 XOpenDevice and XCloseDevice can generate a BadDevice error.

     Structures

	 The XDevice structure returned by XOpenDevice contains:
		      typedef struct {
		      XID device_id;
		      int num_classes;
		      XInputClassInfo *classes;
		      } XDevice;

	 The classes field is a pointer to an array of XInputClassInfo
	 structures. Each element of this array contains an event type
	 base for a class of input supported by the specified device.
	 The num_classes field indicates the number of elements in the
	 classes array.

	 The XInputClassInfo structure contains:

	 typedef struct {
	     unsigned char input_class;
	     unsigned char event_type_base;
	 } XInputClassInfo;

	 The input_class field identifies one class of input supported
	 by the device. Defined types include KeyClass, ButtonClass,
	 ValuatorClass, ProximityClass, FeedbackClass, FocusClass, and
	 OtherClass. The event_type_base identifies the event type of
	 the first event in that class.

	 The information contained in the XInputClassInfo structure is
	 used by macros to obtain the event classes that clients use in
	 making XSelectExtensionEvent requests. Currently defined macros
	 include DeviceKeyPress, DeviceKeyRelease, DeviceButtonPress,
	 DeviceButtonRelease, DeviceMotionNotify, DeviceFocusIn,
	 DeviceFocusOut, ProximityIn, ProximityOut, DeviceStateNotify,
	 DeviceMappingNotify, ChangeDeviceNotify,
	 DevicePointerMotionHint, DeviceButton1Motion,
	 DeviceButton2Motion, DeviceButton3Motion, DeviceButton4Motion,
	 DeviceButton5Motion, DeviceButtonMotion, DeviceOwnerGrabButton,
	 DeviceButtonPressGrab, and NoExtensionEvent.

	 To obtain the proper event class for a particular device, one
	 of the above macros is invoked using the XDevice structure for
	 that device. For example,
		      DeviceKeyPress (*device, type, eventclass);

	 returns the DeviceKeyPress event type and the eventclass for
	 DeviceKeyPress events from the specified device.

	 This eventclass can then be used in an XSelectExtensionEvent
	 request to ask the server to send DeviceKeyPress events from
	 this device. When a selected event is received via XNextEvent,
	 the type can be used for comparison with the type in the event.

DIAGNOSTICS
	 BadDevice
		An invalid device was specified. The specified device
		does not exist, or is the X keyboard or X pointer. This
		error may also occur if some other client has caused the
		specified device to become the X keyboard or X pointer
		device via the XChangeKeyboardDevice or
		XChangePointerDevice requests.

				   05/18/2026			  XOPENDEVICE(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=XCloseDevice&sektion=3&manpath=FreeBSD+Ports+15.1.quarterly>

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