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Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!aluxz!dad
From: dad@aluxz.UUCP (DAPKUS)
Newsgroups: net.micro.pc
Subject: Re: MS-DOS cd command
Message-ID: <256@aluxz.UUCP>
Date: Sun, 9-Jun-85 12:35:17 EDT
Article-I.D.: aluxz.256
Posted: Sun Jun  9 12:35:17 1985
Date-Received: Mon, 10-Jun-85 08:15:58 EDT
References: <2160@mhuxd.UUCP> <1986@watcgl.UUCP>
Organization: AT&T Bell Laboratories, Allentown, PA
Lines: 48

> > Any one know how I might disable the built-in cd command?
> > 
> > Actually, I have two purposes in mind.  One is to allow me to
> > boot my AT&T PC6300 with a menu-driven suite of application
> > programs in such a way that if someone were to get out of the
> > suite, it would be difficult for him/her to go poking around
> > the hard disk and screw up the development stuff I keep in
> > other sub-directories.  The other purpose is to replace the
> > standard cd command with a more Unix(tm)-like version.
> > 
> > In the first case, I guess I want to completely kill the
> > built-in function chdir (and its alias, cd) and in the second,
> > just eliminate the alias.  Any ideas?
> > 
> > Chip
> 
>  A couple of suggestions : 
>  1. I'm not near my system right now to check it out but it may
>     be that MS-DOS checks for name.com, name.exe and name.bat
>     files before it sees if a command is an internal one so that
>     internal commands may be replaced by user versions (of course
>     an intruder could always delete your version and get the system
>     one back... unless it would also work with hidden files).
>  
>  2. Look for the string CD and/or CHDIR in command.com using
>     debug and then change the names to whatever you want.....
>     Now you'll have a secure version of command.com for users

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Chip,

I sent you mail directly, but I must comment on the above message.
Number one will NOT work, as COMMAND.COM looks in itself before
going to disk.  I read the order of .COM, .EXE, and .BAT files,
but I can't find it now.  COMMAND actually puts the .ext on the name,
because if you look at the execute function, you must specify
what the .ext is.  The second method works quite well as I said.


----

					Donald A. Dapkus
					AT&T Bell Laboratories, Allentown, PA
					{ ihnp4, allegra } aluxz!dad

"Ocean: A body of water occupying about two-thirds of a world made
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