{
{   The purpose of this request is to blank out a rectangular area
{ of the screen.  This request also applies a set of visual attributes at
{ all changed screen positions.  Restrictions will be automatically
{ applied to assure that text positions do not receive any of the
{ graphic boldness attributes.  This request is allowed to convert old
{ graphics into text.
{
{       CSP$CLEAR_WORKSPACE_AREA (X_POSITION, Y_POSITION, WIDTH, HEIGHT,
{             ATTRIBUTE, STATUS)
{
{ X_POSITION: (input)  This specifies one of the coordinates for the
{       upper left corner of the area to be affected.
{
{ Y_POSITION: (input)  This is the other coordinate for the upper left
{       corner of the area.
{
{ WIDTH: (input)  This is the horizontal size of the rectangle.
{
{ HEIGHT: (input)  This is the vertical size of the rectangle.
{
{ ATTRIBUTE: (input)  This specifies the attributes to be applied.
{
{ STATUS: (output)  This receives any condition codes.
{
{       condition_identifiers:  cse$workspace_not_open
{                               cse$unknown_x_position
{                               cse$unknown_y_position
