xkbadddeviceledinfo(3) - Linux man page

Name

XkbAddDeviceLedInfo - Initialize an XkbDeviceLedInfoRec structure

Synopsis

XkbDeviceLedInfoPtr XkbAddDeviceLedInfo (XkbDeviceInfoPtr device_info, unsigned int led_class, unsigned int led_id);

Arguments

- 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

Description

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.

Structures

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;

Referenced By

xkballocdeviceledinfo(3)