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XChangeDeviceControl

NAME

XGetDeviceControl, XChangeDeviceControl - query and change input device controls

SYNOPSIS

 #include <X11/extensions/XInput.h>
 

 XDeviceControl *XGetDeviceControl( Display *display,
                                    XDevice *device,
                                    int *controlType);
 

 int XChangeDeviceControl( Display *display,
                           XDevice *device,
                           int controlType,
                           XDeviceControl *control);
 

 display
        Specifies the connection to the X server.
 

 device
        Specifies the device whose control is to be interrogated
        or modified.
 

 controlType
        Specifies the type of control to be interrogated or
        changed.
 

 control
        Specifies the address of an XDeviceControl structure
        that contains the new values for the Device.
 

DESCRIPTION

 These requests are provided to manipulate those input devices
 that support device control. A BadMatch error will be generated
 if the requested device does not support any device controls.
 

 Valid device control types that can be used with these requests
 include the following:
 

 DEVICE_RESOLUTION Queries or changes the resolution of
 valuators on input devices.
 

 The XGetDeviceControl request returns a pointer to an
 XDeviceControl structure.
 

 XGetDeviceControl can generate a BadDevice or BadMatch error.
 

 The XChangeDeviceControl request modifies the values of one
 control on the specified device. The control is identified by
 the id field of the XDeviceControl structure that is passed
 with the request.
 

 XChangeDeviceControl can generate a BadDevice, BadMatch, or
 BadValue error..SH STRUCTURES Each control is described by a
 structure specific to that control. These structures are
 defined in the file XInput.h.
 

 XDeviceControl is a generic structure that contains two fields
 that are at the beginning of each class of control:
 

 typedef struct {
     XID class;
     int length;
 } XDeviceControl;
 

 The XDeviceResolutionState structure defines the information
 that is returned for device resolution for devices with
 valuators.
 

 typedef struct {
     XID control;
     int length;
     int num_valuators;
     int* resolutions;
     int* min_resolutions;
     int* max_resolutions;
 } XDeviceResolutionState;
 

 The XDeviceResolutionControl structure defines the attributes
 that can be controlled for keyboard Devices.
 

 typedef struct {
     XID control;
     int length;
     int first_valuator;
     int num_valuators;
     int* resolutions;
 } XDeviceResolutionControl;
 

DIAGNOSTICS

 BadDevice
        An invalid device was specified. The specified device
        does not exist or has not been opened by this client via
        XOpenInputDevice. This error may also occur if some
        other client has caused the specified device to become
        the X keyboard or X pointer device via the
        XChangeKeyboardDevice or XChangePointerDevice requests.
 

 BadMatch
        This error may occur if an XGetDeviceControl request was
        made specifying a device that has no controls or an
        XChangeDeviceControl request was made with an
        XDeviceControl structure that contains an invalid Device
        type. It may also occur if an invalid combination of
        mask bits is specified ( DvKey but no DvAutoRepeatMode
        for keyboard Devices), or if an invalid KeySym is
        specified for a string Device.
 

 BadValue
        Some numeric value falls outside the range of values
        accepted by the XChangeDeviceControl request. Unless a
        specific range is specified for an argument, the full
        range defined by the argument's type is accepted. Any
        argument defined as a set of alternatives can generate
        this error.