Q67378: OPEN "SCRN:" or "CONS:" Wrong Output in QBX.EXE When Step (F8)

Article: Q67378
Product(s): See article
Version(s): 7.00 7.10
Operating System(s): MS-DOS
Keyword(s): ENDUSER | SR# S901109-37 buglist7.00 buglist7.10 | mspl13_basic
Last Modified: 5-DEC-1990

When you single step (F8) through a program that redirects screen
output to either of the DOS standard devices "SCRN:" or "CONS:", the
output will incorrectly flash momentarily on the QBX.EXE programming
environment, instead of going to the output window.

This problem occurs in the editing environment (QBX.EXE) of Microsoft
BASIC Professional Development System (PDS) versions 7.00 and 7.10.
This problem does not occur in the Microsoft QuickBASIC environment
(QB.EXE) shipped with QuickBASIC version 4.00, 4.00b, and 4.50.
Microsoft is researching this problem and will post new information
here as it becomes available.

The following short program demonstrates the problem:

OPEN "SCRN:" FOR OUTPUT AS #1   ' "CONS:" also shows problem.
FOR i = 1 TO 10
        PRINT #1, i
NEXT i

Single step through this program in the QBX.EXE 7.00 or 7.10
environment by repeatedly pressing the F8 key. The output will
momentarily flash on the environment screen; no text will be displayed
on the output screen. Note that just running the program (F5) will
correctly print to the output screen.

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