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 multiplier.

       accel_numerator
                 Specifies the numerator for the acceleration multiplier.

       accel_numerator_return
                 Returns the numerator for the acceleration multiplier.

       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 fraction may be
       rounded arbitrarily by the X server.  Acceleration only takes effect if the pointer  moves
       more  than threshold pixels at once and only applies to the amount beyond 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 generate this error.

SEE ALSO

       Xlib - C Language X Interface