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From: baird@cod.NOSC.MIL (John M. Baird)
Newsgroups: comp.sys.ibm.pc
Subject: Re: How can I disable Control-C ?
Message-ID: <1553@cod.NOSC.MIL>
Date: 12 Jun 89 14:56:55 GMT
References: <216100099@trsvax>
Organization: Naval Ocean Systems Center, San Diego
Lines: 14

From article <216100099@trsvax>, by snuzs@trsvax.UUCP:
> 	One possibility would be to redirect you autoexec.bat to the NUL
> 	device.
> 	Redirecting the batch file to the NUL device would disable the CON
> 	device i.e. the screen and the keyboard and not allow the user to
> 	Ctlr+Break the autoexec.bat file.
I would suggest you try this before recommending it. On NCR DOS 3.1 (which
I tried the CTTY NUL approach on), keyboard interrupts STILL WORKED. Ctrl-C,
Ctrl-Break, Ctrl-Alt-DEL, etc. Of course, the PC was useless, since no
keyboard commands were read, but Ctrl-C was not disabled. Also, by entering
Ctrl-Break at the right time in the boot process (before the CTTY NUL was
executed), the unfriendly user can still do whatever damage he wants to do.

John Baird, Naval Ocean Systems Center, San Diego