Q67426: Conflict Between CTTY and Command-Line Editing Utilities

Article: Q67426
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:3.x,4.x,5.0
Operating System(s): 
Keyword(s): 
Last Modified: 17-DEC-2000

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The information in this article applies to:

- Microsoft MS-DOS operating system versions 3.1, 3.2, 3.21, 3.3, 3.3a, 4.0, 4.01, 5.0 
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SUMMARY
=======

Command-line editors, such as MS-DOS 5.0 Doskey, may experience problems when a
CTTY command is issued. Command-line editors use system BIOS calls to manipulate
keyboard input and display so they can provide fast, flexible command-line
editing. The CTTY command redirects MS-DOS character input and output calls, but
not system BIOS calls. This can be confusing to command-line editors, producing
unpredictable results.

As a result, DOSKEY and such third-party command-line editors as DOSEDIT, CED,
and PCED should not be used when the CTTY command is executed.

Additional query words: 3.0 3.00 3.1 3.10 3.2 3.20 3.21 3.22 3.3 3.30 3.3a 3.30a 4.0 4.00 4.0a 4.00a 5.00 noupd

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Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS321 kbMSDOS400 kbMSDOS320 kbMSDOS330a kbMSDOS310 kbMSDOS500 kbMSDOS330 kbMSDOS401
Version           : MS-DOS:3.x,4.x,5.0

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