XChangePointerControl(3X11XLIB FUNCTIOXChangePointerControl(3X11)
NAME
XChangePointerControl, XGetPointerControl - control pointer
SYNTAX
int XChangePointerControl(Display *display, Bool do_accel,
Bool do_threshold, int accel_numerator, int
accel_denominator, int threshold);
int XGetPointerControl(Display *display, int
*accel_numerator_return, int *accel_denominator_return,
int *threshold_return);
ARGUMENTS
accel_denominator
Specifies the denominator for the acceleration
multiplier.
accel_denominator_return
Returns the denominator for the acceleration mul-
tiplier.
accel_numerator
Specifies the numerator for the acceleration mul-
tiplier.
accel_numerator_return
Returns the numerator for the acceleration multi-
plier.
display Specifies the connection to the X server.
do_accel Specifies a Boolean value that controls whether
the values for the accel_numerator or
accel_denominator are used.
do_threshold
Specifies a Boolean value that controls whether
the value for the threshold is used.
threshold Specifies the acceleration threshold.
threshold_return
Returns the acceleration threshold.
DESCRIPTION
The XChangePointerControl function defines how the pointing
device moves. The acceleration, expressed as a fraction, is
a multiplier for movement. For example, specifying 3/1 means
the pointer moves three times as fast as normal. The frac-
tion may be rounded arbitrarily by the X server. Accelera-
tion only takes effect if the pointer moves more than thres-
hold pixels at once and only applies to the amount beyond
XFree86 Version 4.5.0 1
XChangePointerControl(3X11XLIB FUNCTIOXChangePointerControl(3X11)
the value in the threshold argument. Setting a value to -1
restores the default. The values of the do_accel and
do_threshold arguments must be True for the pointer values
to be set, or the parameters are unchanged. Negative values
(other than -1) generate a BadValue error, as does a zero
value for the accel_denominator argument.
XChangePointerControl can generate a BadValue error.
The XGetPointerControl function returns the pointer's
current acceleration multiplier and acceleration threshold.
DIAGNOSTICS
BadValue Some numeric value falls outside the range of
values accepted by the 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 gen-
erate this error.
SEE ALSO
Xlib - C Language X Interface
XFree86 Version 4.5.0 2