Save whole screen image and coordinate to an internal buffer
__XSaveScreen() save the image of the whole screen into an internal buffer, it also save current cursor position. The information could later be restored by __XRestScreen(). Each call to __XSaveScreen() overwrite the internal buffer.
SAVE SCREEN command is preprocessed into __XSaveScreen() function during compile time. Note that SAVE SCREEN TO is preprocessed into SaveScreen() function.
__XSaveScreen() is a compatibility function, it is superseded by SaveScreen() which allow you to save part or all the screen into a variable.
// save the screen, display list of files than restore the screen SAVE SCREEN DIR *.* WAIT RESTORE SCREEN
Library is core
RESTORE SCREEN, RestScreen(), SaveScreen()