Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!osu-cis!sppy00!jmv
From: jmv@sppy00.UUCP (Jim Vickroy)
Newsgroups: comp.sys.ibm.pc
Subject: Re: CTRL-ALT-DEL key
Message-ID: <234@sppy00.UUCP>
Date: 30 Mar 89 19:48:14 GMT
References: <1623@arctic.nprdc.arpa> <3818@nicmad.UUCP>
Reply-To: jmv@sppy00.UUCP (Jim Vickroy)
Distribution: na
Organization: Online Computer Library Center, Dublin, Ohio.
Lines: 45

=>In article <1623@arctic.nprdc.arpa> snguyen@nprdc.arpa (Son Nguyen) writes:
=>
=>Hello, every one.
=>
=>	I just wonder if (possibly done) we could write a program to
=>detect the pressing of these three keys: CTRL-ALT-DEL.   In other words,
=>can I write a software in the "C" language or in IBM assembly language to
=>detect and maybe disable them  ?   You may say that I am a little crazy.
=>The reason I would like to achieve so is because I would like to implement
=>a password program hat allows only the authorized users to access my IBM
=>PC XT computer.  I know how to disable the interrupts but my friends are
=>smarter.  When they turn on my computer and notice that I have installed
=>this program, they then press the keys CTRL-ALT-KEY and insert their own
=>MS-DOS disk on the drive A:.  It may seem silly that why they don't put
=>their system disk initially when they try o turn it on.  Well,  that is
=>another problem.  This raises my second question:  Can we configure the
=>computer to boot only with "C:" drive ?	
=>
=>PS:  Please, don't tell me to buy an IBM AT which
=>has the key lock.  My questions are posted to achiee both
=>points: for learning, and for my IBM PC  protection.
=>

I don't think you're crazy. There are *very* good reasons for disabling the
softboot keys. Systems which maintain database can't tolerate a reboot right
in the middle of an update, for example. At any rate, to disable this key
press you will have to write your own keyboard interrupt handler. A formidable
task indeed! Essentially you will have to 'steal' interrupts 9 and 16 hex
and watch for that keypress and throw it away when you get it.

In order to have your machine boot only from C: will require your own
bootstrap. 

Good luck

P.S. Have you thought about bodily harm?


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! Jim Vickroy                          | cbosgd!osu-cis!sppy00!jmv !/././././!
! Online Computer Library Center, Inc. |---------------------------!././././.!
! Dublin, Ohio  43017                  | jmv@sppy00                !/././././!
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! "That voodoo stuff don't do nothin' for me"                 -jrr !/././././!
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