1	FUNCTION BYTE SMG_YES_NO(STRING Prompt,LONG Row,LONG Col,	&
		BYTE Default_Response,LONG Timeout,BYTE Vir_disp_num)

	!---------------------------------------------------------------&
	!								&
	!			  SMG_YES_NO				&
	!								&
	!		Creation Date:  2-Oct-1985			&
	!		Author:		Ken Messer			&
	! 		Purpose:        Prompt user with a yes/no	&
	!				question and take yes, no, or	&
	!				a supplied default response as	&
	!				input.				&
	!								&
	!		Modification history				&
	!								&
	!	Date	Description of change(s)			&
	!								&
	!---------------------------------------------------------------&
	!								&
	! Copyright (c) 1985 -	Ken Messer, Allied Electronics, Inc.,	&
	!			401 E. 8th St., Ft. Worth, TX  76102	&
	!								&
	! This software may be copied and distributed freely to anyone	&
	! for non-commerical use provided that this copyright notice is &
	! included.							&
	!---------------------------------------------------------------&

	OPTION TYPE = INTEGER, SIZE = INTEGER LONG

	%include "SMG$LIBRARY:SMG.DFN"

	!---------------------------------------------------------------&
	!								&
	!		D a t a   D e c l a r a t i o n s		&
	!								&
	!---------------------------------------------------------------&

	DECLARE BYTE CONSTANT		Yes = -1,			&
					No = 0

	DECLARE WORD			Term_code

	DECLARE LONG			RS,				&
					Readcol,			&
					Display_rows,			&
					Display_cols,			&
					Def_disp_attr,			&
					Def_video_attr

	EXTERNAL LONG CONSTANT		SS$_Normal,			&
					SMG$M_Bold

	EXTERNAL LONG FUNCTION		SMG$Read_Keystroke,		&
					SMG$Set_cursor_abs,		&
					SMG$Ring_bell,			&
					SMG$Put_chars,			&
					SMG$Get_display_attr,		&
					SMG$Change_virtual_display,	&
					SMG$Erase_line

	EXTERNAL STRING FUNCTION	Get_Error_Message(LONG)

	!---------------------------------------------------------------&
	!								&
	!		M a i n   P r o g r a m   L o g i c		&
	!								&
	!---------------------------------------------------------------&

	! Set up the input string read column

	SELECT LEN(Prompt)
	   CASE 0
		Readcol = Col
	   CASE ELSE
		Readcol = Col + LEN(Prompt) + 1
	END SELECT

100	! print the prompt

	RS = SMG$Put_chars(Display_id(Vir_disp_num),Prompt,Row,Col,,,,)

	IF RS AND SS$_Normal = 0   THEN
		PRINT Get_Error_Message(RS)
		STOP
	END IF

200	! get current default display attributes so we will know what
	! to change back to later

	RS = SMG$Get_display_attr(Display_id(Vir_disp_num),Display_rows, &
		Display_cols,Def_disp_attr,Def_video_attr,)

	IF RS AND SS$_Normal = 0   THEN
		PRINT Get_Error_Message(RS)
		STOP
	END IF

300	! make default video attribute bold reverse video

	RS = SMG$Change_virtual_display(Display_id(Vir_disp_num),	&
		Display_rows,Display_cols,Def_disp_attr,		&
		Input_Display_attr OR SMG$M_Bold,)

	IF RS AND SS$_Normal = 0   THEN
		PRINT Get_Error_Message(RS)
		STOP
	END IF

 Get_Input:

400	! print the default response on the display - default to NO if
	! something other than Yes or No is passed in

	SELECT Default_Response
	   CASE Yes
		RS = SMG$Put_chars(Display_id(Vir_disp_num),"Y",Row,	&
		   Readcol,,,,)
	   CASE ELSE
		RS = SMG$Put_chars(Display_id(Vir_disp_num),"N",Row,	&
		   Readcol,,,,)
	END SELECT

	IF RS AND SS$_Normal = 0   THEN
		PRINT Get_Error_Message(RS)
		STOP
	END IF

500	! reset the cursor

	RS = SMG$Set_cursor_abs(Display_id(Vir_disp_num),Row,Readcol)

	IF RS AND SS$_Normal = 0   THEN
		PRINT Get_Error_Message(RS)
		STOP
	END IF

600	! Do the input

	IF Timeout > 0	THEN
	   RS = SMG$Read_Keystroke(Current_keyboard_id,Term_code,,	&
		Timeout,Display_id(Vir_disp_num))
	ELSE
	   RS = SMG$Read_Keystroke(Current_keyboard_id,Term_code,,,	&
		Display_id(Vir_disp_num))
	END IF

700	SELECT Term_code

		CASE 13		! carriage return

			SMG_YES_NO = Default_Response

		CASE 78,110	! N,n

			SMG_YES_NO = No

		CASE 89,121	! Y,y

			SMG_YES_NO = Yes

		CASE 509	! Timeout - flag it back as having happened
				! Take the default

			Timeout = -1
			SMG_YES_NO = Default_Response

		CASE ELSE	! Nothing else allowed - ring bell and go back

			RS = SMG$Ring_bell(Display_id(Vir_disp_num),1)

			IF RS AND SS$_Normal = 0   THEN
				PRINT Get_Error_Message(RS)
				STOP
			END IF

			GOTO Get_Input

	END SELECT

32000	Timeout = 0	UNLESS Timeout = -1

	! change back to original video rendition

	RS = SMG$Change_virtual_display(Display_id(Vir_disp_num),	&
		Display_rows,Display_cols,Def_disp_attr,Def_video_attr,)

	IF RS AND SS$_Normal = 0   THEN
		PRINT Get_Error_Message(RS)
		STOP
	END IF

	! clear the line

	RS = SMG$Erase_line(Display_id(Vir_disp_num),Row,Col)

	IF RS AND SS$_Normal = 0   THEN
		PRINT Get_Error_Message(RS)
		STOP
	END IF

32767	EXIT FUNCTION

	END FUNCTION