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From: new@ee.udel.edu (Darren New)
Newsgroups: comp.os.misc
Subject: Re: What constitutes a good OS?
Message-ID: <42377@nigel.ee.udel.edu>
Date: 22 Jan 91 01:53:49 GMT
References: <5392@auspex.auspex.com> <42346@nigel.ee.udel.edu> <1991Jan21.235826.7250@Think.COM>
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In article <1991Jan21.235826.7250@Think.COM> barmar@think.com (Barry Margolin) writes:
>Even on systems where line numbers are keys, you still need to rewrite a
>file in order to insert a change in the middle.  

Not at all.  You either rewrite the record in place (if it is the same
or smaller length) or you put the new record at the end and point the
old key to it. How else would you be able to insert a record in the 
middle without rewriting the entire file? Granted, sometimes inserting
a key could require several new blocks of keys to be added to the file
(like when one of the keyblocks fills up) but that is exceptional.
		     -- Darren

-- 
--- Darren New --- Grad Student --- CIS --- Univ. of Delaware ---
----- Network Protocols, Graphics, Programming Languages, 
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              =+=+=+ Let GROPE be an N-tuple where ... +=+=+=