{
{   The purpose of this request is to update the screen with any output
{ operations not yet physically output from the interfaces csp$draw_lines,
{ csp$change_workspace_attributes, csp$change_workspace_text,
{ csp$set_workspace_cursor, csp$clear_workspace_area, or csp$open_workspace.
{ Then input is requested and the device driver will calculate the net
{ effect of minor keystrokes such as overtyping, cursor motion, and
{ insertion or deletion of characters.  This request completes when the
{ input stream contains a keystrokes significant enough to be processed
{ by the application.  Future calls to CSP$ACCEPT_INPUT will continue
{ scanning the input record until it is exhausted, then another screen
{ update and device read will be performed.
{
{       CSP$ACCEPT_INPUT (CONTROL, X_POSITION, Y_POSITION, STATUS)
{
{ CONTROL: (output) This describes the significant keystroke which
{       caused scanning of the input to pause for application
{       processing.
{
{ X_POSITION: (output) This describes one of the cursor coordinates
{       at which the CONTROL event was encountered.
{
{ Y_POSITION: (output) This is the other coordinate.
{
{ STATUS: (output) This parameter receives any error conditions.
{
{       condition identifiers:  cse$workspace_not_open
{                               cse$corrupted_terminal_table
