To change characteristics of an X Input Extension device in the server, first modify a local copy of the device structure and then use either XkbSetDeviceInfo, or, to save network traffic, use an XkbDeviceChangesRec structure and call XkbChangeDeviceInfo to download the changes to the server.
XkbSetDeviceInfo
sends a request to the server to modify the characteristics of the device
specified in the device_info structure. The particular characteristics
modified are identified by the bits set in which and take their values
from the relevant fields in device_info (see Table 1). XkbSetDeviceInfo
returns True if the request was successfully sent to the server. If the
X server implementation does not allow interaction between the X input
extension and the Xkb Extension, the function does nothing and returns
False.
Table 1 XkbDeviceInfoRec Mask Bits ____________________________________________________________________________________ Name XkbDeviceInfoRec Value Capability If Set Fields Effected ____________________________________________________________________________________ XkbXI_KeyboardsMask (1L <<0) Clients can use all Xkb requests and events with KeyClass devices supported by the input device extension. XkbXI_ButtonActionsMask num_btns (1L <<1) Clients can assign key btn_acts actions to buttons non-KeyClass input extension devices. XkbXI_IndicatorNamesMask leds->names (1L <<2) Clients can assign names to indicators on non-KeyClass input extension devices. XkbXI_IndicatorMapsMask leds->maps (1L <<3) Clients can assign indicator maps to indicators on non-KeyClass input extension devices. XkbXI_IndicatorStateMask leds->state (1L <<4) Clients can request the status of indicators on non-KeyClass input extension devices. XkbXI_IndicatorsMask sz_leds (0x1c) XkbXI_IndicatorNamesMask | num_leds XkbXI_IndicatorMapsMask | leds->* XkbXI_IndicatorStateMask XkbXI_UnsupportedFeaturesMask unsupported (1L <<15) XkbXI_AllDeviceFeaturesMask Those selected (0x1e) XkbXI_IndicatorsMask | by Value Column XkbSI_ButtonActionsMask masks XkbXI_AllFeaturesMask Those selected (0x1f) XkbSI_AllDeviceFeaturesMask | by Value Column XkbSI_KeyboardsMask masks XkbXI_AllDetailsMask Those selected (0x801f) XkbXI_AllFeaturesMask | by Value column XkbXI_UnsupportedFeaturesMask masks
The which parameter specifies which aspects of the device should be
changed and is a bitmask composed of an inclusive OR or one or more of
the following bits: XkbXI_ButtonActionsMask, XkbXI_IndicatorNamesMask,
XkbXI_IndicatorMapsMask. If the features requested to be manipulated in
which are valid for the device, but the server does not support assignment
of one or more of them, that particular portion of the request is ignored.
If the device specified in device_info->device_spec does not contain buttons
and a request affecting buttons is made, or the device does not contain
indicators and a request affecting indicators is made, a BadMatch protocol
error results.
If the XkbXI_ButtonActionsMask bit is set in the supported mask returned by XkbGetDeviceInfo, the Xkb extension allows applications to assign key actions to buttons on input extension devices other than the core keyboard device. If the XkbXI_ButtonActionsMask is set in which, the actions for all buttons specified in device_info are set to the XkbActions specified in device_info->btn_acts. If the number of buttons requested to be updated is not valid for the device, XkbSetDeviceInfo returns False and a BadValue protocol error results.
If the XkbXI_IndicatorMaps
and / or XkbXI_IndicatorNamesMask bit is set in the supported mask returned
by XkbGetDeviceInfo, the Xkb extension allows applications to assign
maps and / or names to the indicators of nonkeyboard extension devices.
If supported, maps and / or names can be assigned to all extension device
indicators, whether they are part of a keyboard feedback or part of an
indicator feedback.
If the XkbXI_IndicatorMapsMask and / or XkbXI_IndicatorNamesMask flag
is set in which, the indicator maps and / or names for all device_info->num_leds
indicator devices specified in device_info->leds are set to the maps and
/ or names specified in device_info->leds. device_info->leds->led_class and
led_id specify the input extension class and device ID for each indicator
device to modify; if they have invalid values, a BadValue protocol error
results and XkbSetDeviceInfo returns False. If they have legal values
but do not specify a keyboard or indicator class feedback for the device
in question, a BadMatch error results. If any of the values in device_info->leds->names
are not a valid Atom or None, a BadAtom protocol error results.
Changes
to an Xkb extension device may be tracked by listening to XkbDeviceExtensionNotify
events and accumulating the changes in an XkbDeviceChangesRec structure.
The changes noted in the structure may then be used in subsequent operations
to update either a server configuration or a local copy of an Xkb extension
device configuration. The changes structure is defined as follows:
typedef struct _XkbDeviceChanges { unsigned int changed; /* bits indicating what has changed */ unsigned short first_btn; /* number of first button which changed, if any */ unsigned short num_btns; /* number of buttons that have changed */ XkbDeviceLedChangesRec leds; } XkbDeviceChangesRec,*XkbDeviceChangesPtr;