1 XLISTINPUTDEVICES(libmansuffix)
2 ===============================
7 XListInputDevices, XFreeDeviceList - list available input
13 #include <X11/extensions/XInput.h>
15 XDeviceInfo *XListInputDevices( Display *display,
16 int *ndevices_return);
18 int XFreeDeviceList( XDeviceInfo *list);
21 Specifies the connection to the X server.
24 Specifies a pointer to a variable where the number of
25 available devices canbe returned.
28 Specifies the list of devices to free. The
29 XFreeDeviceList functionfrees the list of available
30 extension input devices.
35 The XListInputDevices request lists the available input
36 devices. This list includes the core keyboard and any physical
37 input device currently accessible through the X server, and any
38 input devices that are not currently accessible through the X
39 server but could be accessed if requested.
41 A master pointer is a virtual pointer device that does not
42 represent a physical device. It is visually represented through
43 a cursor. A master keyboard is a virtual keyboard device that
44 does not represent a physical device. It is virtually
45 representd through a keyboard focus. A master pointer and a
46 master keyboard are always paired (i.e. if shift is pressed on
47 the master keyboard, a pointer click would be a shift-click).
48 Multiple master pointer/keyboard pairs can exist.
50 X servers supporting the X Input Extension version 2,
51 XListInputDevices only returns the first master pointer, the
52 first master keyboard and all slave devices. Additional master
53 devices are not listed.
55 Physical devices (so-called slave devices) are attached to
56 either a master pointer or a master keyboard, depending on
57 their capabilities. If a slave device generates an event, the
58 event is also generated by the respective master device.
59 Multiple slave devices can be attached to a single master
62 Some server implementations may make all physical input devices
63 available at the time the server is initialized. Others may
64 wait until requested by a client to access an input device. In
65 the latter case, it is possible that an input device will be
66 listed as available at one time but not at another.
68 For each input device available to the server, the
69 XListInputDevices request returns an XDeviceInfo structure.
70 That structure contains a pointer to a list of structures, each
71 of which contains information about one class of input
72 supported by the device. The XDeviceInfo structure is defined
74 typedef struct _XDeviceInfo {
80 XAnyClassPtr inputclassinfo;
83 The id is a number in the range 0-128 that uniquely identifies
84 the device. It is assigned to the device when it is initialized
87 The type field is of type Atom and indicates the nature of the
88 device. The type will correspond to one of the following strings
89 (defined in the header file XI.h):
91 XI_MOUSE XI_TABLET XI_KEYBOARD XI_TOUCHSCREEN XI_TOUCHPAD
92 XI_BUTTONBOX XI_BARCODE XI_TRACKBALL XI_QUADRATURE XI_ID_MODULE
93 XI_ONE_KNOB XI_NINE_KNOB XI_KNOB_BOX XI_SPACEBALL XI_DATAGLOVE
94 XI_EYETRACKER XI_CURSORKEYS XI_FOOTMOUSE XI_JOYSTICK
96 These strings may be used in an XInternAtom request to return
97 an atom that can be compared with the type field of the
98 XDeviceInfo structure.
100 The name field contains a pointer to a null-terminated string
101 that serves as identifier of the device. This identifier may be
102 user-configured or automatically assigned by the server.
104 The num_classes field is a number in the range 0-255 that
105 specifies the number of input classes supported by the device
106 for which information is returned by ListInputDevices. Some
107 input classes, such as class Focus and class Proximity do not
108 have any information to be returned by ListInputDevices.
110 All devices provide an AttachClass. This class specifies the
111 master device a given slave device is attached to. For master
112 devices, the class specifies the respective paired master
115 The use field specifies how the device is currently being used.
116 If the value is IsXKeyboard, the device is a master keyboard.
117 If the value is IsXPointer, the device is a master pointer. If
118 the value is IsXExtensionPointer, the device is a slave
119 pointer. If the value is IsXExtensionKeyboard, the device is a
120 slave keyboard. If the value is IsXExtensionDevice, the device
121 is available for use as an extension device.
123 The inputclassinfo field contains a pointer to the first
124 input-class specific data. The first two fields are common to
127 The class field is a number in the range 0-255. It uniquely
128 identifies the class of input for which information is
129 returned. Currently defined classes are KeyClass, ButtonClass,
132 The length field is a number in the range 0- 255. It specifies
133 the number of bytes of data that are contained in this input
134 class. The length includes the class and length fields.
136 The XKeyInfo structure describes the characteristics of the
137 keys on the device. It is defined as follows:
139 typedef struct _XKeyInfo {
142 unsigned short min_keycode;
143 unsigned short max_keycode;
144 unsigned short num_keys;
148 min_keycode is of type KEYCODE. It specifies the minimum
149 keycode that the device will report. The minimum keycode will
150 not be smaller than 8.
152 max_keycode is of type KEYCODE. It specifies the maximum
153 keycode that the device will report. The maximum keycode will
154 not be larger than 255.
156 num_keys specifies the number of keys that the device has.
158 The XButtonInfo structure defines the characteristics of the
159 buttons on the device. It is defined as follows:
161 typedef struct _XButtonInfo {
167 num_buttons specifies the number of buttons that the device
170 The XValuatorInfo structure defines the characteristics of the
171 valuators on the device. It is defined as follows:
173 typedef struct _XValuatorInfo {
176 unsigned char num_axes;
178 unsigned long motion_buffer;
182 num_axes contains the number of axes the device supports.
184 mode is a constant that has one of the following values:
185 Absolute or Relative. Some devices allow the mode to be changed
186 dynamically via the SetDeviceMode request.
188 motion_buffer_size is a cardinal number that specifies the
189 number of elements that can be contained in the motion history
190 buffer for the device.
192 The axes field contains a pointer to an XAxisInfo structure.
194 The XAxisInfo structure is defined as follows:
196 typedef struct _XAxisInfo {
202 The resolution contains a number in counts/meter.
204 The min_val field contains a number that specifies the minimum
205 value the device reports for this axis. For devices whose mode
206 is Relative, the min_val field will contain 0.
208 The max_val field contains a number that specifies the maximum
209 value the device reports for this axis. For devices whose mode
210 is Relative, the max_val field will contain 0.
212 The XAttachInfo structure is defined as follows:
213 typedef struct _XAttachInfo {
217 If the device is a slave device, attached specifies the device
218 ID of the master device this device is attached to. If the
219 device is not attached to a master device, attached is
220 Floating. If the device is a master device, attached specifies
221 the device ID of the master device this device is paired with.
223 To free the XDeviceInfo array created by XListInputDevices, use