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Date:      Thu, 07 Dec 1995 16:54:53 -0600
From:      John Goerzen <jgoerzen@complete.org>
To:        questions@freebsd.org
Subject:   Re: ****HELP***** 
Message-ID:  <199512072254.QAA01033@complete.org>
In-Reply-To: Your message of "Wed, 06 Dec 1995 16:20:09 MST." <199512062320.QAA19749@intele.net> 

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> Obviously not very experienced with UNIX.  If any of the programs
> you are attempting to overwrite happen to be running, you won't be
> able to open them for writing, even as root.  You'll obtain EBUSY

Why would they be running if you boot of the install floppy?

> (text file busy).  What you have to do is unlink the file (it won't
> really be reclaimed until closed, i.e. the program exits) and then
> create the new file with the same name.  This, of course, leaves
> you with a small window of vulnerability where /bin/sh (and so
> forth) does not exist!  It also has the side effect of fragging
> your disk badly.  This is one of the many reasons most UNIX updates
> are done off-line, in single user mode, or booted from an alternate
> kernel ala Sun's miniroot.

It would seem to me that to overwrite a file _should_ make the change 
in-place, that is, without having to delete, recreate, etc.  At least, that's 
what DOS and OS/2 do, and I wonder why FreeBSD would be worse?

-- John

-- 
John Goerzen, programmer and owner   | MICRO$oft only exists because some
Communications Centre & Complete BBS | people are too dumb to get something
E-mail jgoerzen@complete.org         | better, such as FreeBSD.





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