]> XkbAddDeviceLedInfo




XkbAddDeviceLedInfo − Initialize an XkbDeviceLedInfoRec structure


XkbDeviceLedInfoPtr XkbAddDeviceLedInfo

(XkbDeviceInfoPtr device_info,

unsigned int led_class, unsigned int led_id);


− device_info

structure in which to add LED info

− led_class

input extension class for LED device of interest

− led_id

input extension ID for LED device of interest


XkbAddDeviceLedInfo first checks to see whether an entry matching led_class and led_id already exists in the device_info->leds array. If it finds a matching entry, it returns a pointer to that entry. Otherwise, it checks to be sure there is at least one empty entry in device_info->leds and extends it if there is not enough room. It then increments device_info->num_leds and fills in the next available entry in device_info->leds with led_class and led_id.

If successful, XkbAddDeviceLedInfo returns a pointer to the XkbDeviceLedInfoRec structure that was initialized. If unable to allocate sufficient storage, or if device_info points to an invalid XkbDeviceInfoRec structure, or if led_class or led_id are inappropriate, XkbAddDeviceLedInfo returns NULL.

To allocate additional space for button actions in an XkbDeviceInfoRec structure, use XkbResizeDeviceButtonActions.


Information about X Input Extension devices is transferred between a client program and the Xkb extension in an XkbDeviceInfoRec structure:

typedef struct {
char * name; /∗ name for device */
Atom type; /∗ name for class of devices */
unsigned short device_spec; /∗ device of interest */
Bool has_own_state; /∗ True=>this device has its own state */
unsigned short supported; /∗ bits indicating supported capabilities */
unsigned short unsupported; /∗ bits indicating unsupported capabilities */
unsigned short num_btns; /∗ number of entries in btn_acts */
XkbAction * btn_acts; /∗ button actions */
unsigned short sz_leds; /∗ total number of entries in LEDs vector */
unsigned short num_leds; /∗ number of valid entries in LEDs vector */
unsigned short dflt_kbd_fb; /∗ input extension ID of default (core kbd) indicator */
unsigned short dflt_led_fb; /∗ input extension ID of default indicator feedback */
XkbDeviceLedInfoPtr leds; /∗ LED descriptions */
} XkbDeviceInfoRec, *XkbDeviceInfoPtr;

typedef struct {
unsigned short led_class; /∗ class for this LED device*/
unsigned short led_id; /∗ ID for this LED device */
unsigned int phys_indicators; /∗ bits for which LEDs physically present */
unsigned int maps_present; /∗ bits for which LEDs have maps in maps */
unsigned int names_present; /∗ bits for which LEDs are in names */
unsigned int state; /∗ 1 bit => corresponding LED is on */
Atom names[XkbNumIndicators]; /∗ names for LEDs */
XkbIndicatorMapRec maps; /∗ indicator maps for each LED */
} XkbDeviceLedInfoRec, *XkbDeviceLedInfoPtr;