Q35888: CTRL+PRINT SCREEN Fails in EXE Compiled with BCOM Library

Article: Q35888
Product(s): See article
Version(s): 4.00 4.00b 4.50
Operating System(s): MS-DOS
Keyword(s): ENDUSER | buglist4.00 buglist4.00b buglist4.50 B_BasicCom | mspl13_basic
Last Modified: 14-DEC-1989

CTRL+PRINT SCREEN works correctly from a program compiled with the
QuickBASIC BRUN4x.LIB library or run in the QB.EXE editor but fails to
send output to the printer in a program compiled to a stand-alone
module with the BC /O option (BCOM4x.LIB). The problem worsens if you
compile with the Debug option in addition to /O; pressing CTRL+PRINT
SCREEN then causes subsequent screen output to be truncated, and no
output goes to the printer.

Microsoft has confirmed this to be a problem in QuickBASIC Versions
4.00, 4.00b, and 4.50 and in Microsoft BASIC Compiler Versions 6.00
and 6.00b for MS-DOS (buglist6.00, buglist6.00b). This problem was
corrected in Microsoft BASIC PDS Version 7.00 (fixlist7.00).

The problem does not occur in programs compiled in QuickBASIC Version
3.00. CTRL+PRINT SCREEN works correctly in QuickBASIC Version 3.00.
Pressing CTRL+PRINT SCREEN in MS-DOS normally acts as a toggle to turn
on (or off) the redirection of screen output to the printer.

The following is a code example:

10 PRINT "Please press CTRL-PRTSC (or CONTROL+PRINT SCREEN):"
15 FOR i = 1 TO 5
20 INPUT "Enter text:"; a$
25 NEXT