XmScaleSetValue - Man Page
A Scale function that sets a slider value
Synopsis
#include <Xm/Scale.h> void XmScaleSetValue( Widget widget, int value);
Description
XmScaleSetValue sets the slider value within the Scale widget.
- widget
- Specifies the Scale widget ID. 
- value
- Specifies the slider position along the scale. This sets the XmNvalue resource. 
For a complete definition of Scale and its associated resources, see XmScale(3).