CTRL+PRINT SCREEN Fails in EXE Compiled with BCOM Library (35888)

SYMPTOMS

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.

STATUS

Microsoft has confirmed this to be a bug 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.

MORE INFORMATION

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