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From: barmar@think.com (Barry Margolin)
Newsgroups: comp.os.misc
Subject: Re: What constitutes a good OS?
Message-ID: <1991Jan21.235826.7250@Think.COM>
Date: 21 Jan 91 23:58:26 GMT
References: <42128@nigel.ee.udel.edu> <5392@auspex.auspex.com> <42346@nigel.ee.udel.edu>
Sender: news@Think.COM
Organization: Thinking Machines Corporation, Cambridge MA, USA
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In article <42346@nigel.ee.udel.edu> new@ee.udel.edu (Darren New) writes:
>What a shame. Then editors have to read an entire file and then write it
>back out again to make one change in the middle. The line numbers become
>the equivalent of card sequence numbers. Yuk.

Even on systems where line numbers are keys, you still need to rewrite a
file in order to insert a change in the middle.  Unless the file is
implemented as a linked list of records, but I've never heard of a system
that does this for ordinary (i.e. non-DBMS) files.  The filesystem might
hide this rewriting from the application, but it still has to be done.
--
Barry Margolin, Thinking Machines Corp.

barmar@think.com
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