XGetFeedbackControl(), XChangeFeedbackControl() - query and change input device feedbacks
XFeedbackState *XGetFeedbackControl (Display *display,
XDevice *device,
int *num_feedbacks)
int XChangeFeedbackControl (Display *display, XDevice *device,
Mask mask, XFeedbackControl *control )
These requests are provided to manipulate those input devices that support feedbacks. A BadMatch error will be generated if the requested device does not support feedbacks. Whether or not a given device supports feedbacks can be determined by examining the information returned by the XOpenDevice(3) request. For those devices that support feedbacks, XOpenDevice(3) will return XInputClassInfo structure with the input_class field equal to the constant FeedbackClass (defined in the file <X11/XI.h>).
The XGetFeedbackControl(3) request returns a pointer to a list of XFeedbackState structures. Each item in this list describes one of the feedbacks supported by the device. The items are variable length, so each contains its length to allow traversal to the next item in the list.
The feedback classes that are currently defined are: KbdFeedbackClass, PtrFeedbackClass, StringFeedbackClass, IntegerFeedbackClass, LedFeedbackClass, and BellFeedbackClass. These constants are defined in the file <X11/XI.h>. An input device may support zero or more classes of feedback, and may support multiple feedbacks of the same class. Each feedback contains a class identifier and an id that is unique within that class for that input device. The id is used to identify the feedback when making an XChangeFeedbackControl(3) request.
XGetFeedbackControl(3) can generate a BadDevice or BadMatch error.
The XChangeFeedbackControl(3) request modifies the values of one feedback on the specified device. The feedback is identified by the id field of the XFeedbackControl structure that is passed with the request. The fields of the feedback that are to be modified are identified by the bits of the mask that is passed with the request.
XChangeFeedbackControl(3) can generate a BadDevice, BadMatch, or BadValue error.
Each class of feedback is described by a structure specific to that class. These structures are defined in the file <X11/extensions/XInput.h>. XFeedbackState and XFeedbackControl are generic structures that contain three fields that are at the beginning of each class of feedback:
typedef struct { XID class; int length; XID
id; } XFeedbackState, XFeedbackControl;
The XKbdFeedbackState structure defines the attributes that are returned for feedbacks equivalent to those on the X keyboard.
typedef struct {
XID class;
int length;
XID id;
int click;
int percent;
int pitch;
int duration;
int led_mask;
int global_auto_repeat;
char auto_repeats[32];
} XKbdFeedbackState;
The XPtrFeedbackState structure defines the attributes that are returned for feedbacks equivalent to those on the X pointer.
typedef struct {
XID class;
int length;
XID id;
int accelNum;
int accelDenom;
int threshold;
} XPtrFeedbackState;
The XIntegerFeedbackState structure defines attributes that are returned for integer feedbacks.
typedef struct {
XID class;
int length;
XID id;
int resolution;
int minVal;
int maxVal;
} XIntegerFeedbackState;
The XStringFeedbackState structure defines the attributes that are returned for string feedbacks.
typedef struct {
XID class;
int length;
XID id;
int max_symbols;
int num_syms_supported;
KeySym *syms_supported;
} XStringFeedbackState;
The XBellFeedbackState structure defines the attributes that are returned for bell feedbacks.
typedef struct {
XID class;
int length;
XID id;
int percent;
int pitch;
int duration;
} XBellFeedbackState;
The XLedFeedbackState structure defines the attributes that are returned for LED feedbacks.
typedef struct {
XID class;
int length;
XID id;
int led_values;
} XLedFeedbackState;
The XPrtFeedbackControl structure defines the attributes that can be controlled for pointer feedbacks.
typedef struct {
XID class;
int length;
XID id;
int accelNum;
int accelDenom;
int threshold;
} XPtrFeedbackControl;
The XKbdFeedbackControl structure defines the attributes that can be controlled for keyboard feedbacks.
typedef struct {
XID class;
int length;
XID id;
int click;
int percent;
int pitch;
int duration;
int led_mask;
int led_value;
int key;
int auto_repeat_mode;
} XKbdFeedbackControl;
The XStringFeedbackControl structure defines the attributes that can be controlled for string feedbacks.
typedef struct {
XID class;
int length;
XID id;
int num_keysyms;
KeySym *syms_to_display;
} XStringFeedbackControl;
The XIntegerFeedbackControl structure defines the attributes that can be controlled for integer feedbacks.
typedef struct {
XID class;
int length;
XID id;
int int_to_display;
} XIntegerFeedbackControl;
The XBellFeedbackControl structure defines the attributes that can be controlled for bell feedbacks.
typedef struct {
XID class;
int length;
XID id;
int percent;
int pitch;
int duration;
} XBellFeedbackControl;
The XLedFeedbackControl structure defines the attributes that can be controlled for LED feedbacks.
typedef struct {
XID class;
int length;
XID id;
int led_mask;
int led_values;
} XLedFeedbackControl;
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