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From: brooks@lll-crg.ARPA (Eugene D. Brooks III)
Newsgroups: net.lang.c
Subject: Re: Re: more questions about efficient C code
Message-ID: <665@lll-crg.ARPA>
Date: Thu, 27-Jun-85 22:47:10 EDT
Article-I.D.: lll-crg.665
Posted: Thu Jun 27 22:47:10 1985
Date-Received: Sat, 29-Jun-85 03:27:10 EDT
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Distribution: net
Organization: Lawrence Livermore Labs, CRG group
Lines: 17

> >>	if ((fp = fopen("foo", "r") == NULL) {
> 	This example bothers me.  I'm not sure what all makes up the
> 	fopen subroutine, but the addition or subtraction of one measely
> 	assignment statement *has* to be negligible when compared to what
> 	goes on in fopen.  Even if that code is in the innermost of inner
> 	loops, the "optimization" will still be unnoticable.  I know
> 	it's just an example of an assignment within a boolean expression,
> 	but I see a *lot* of programs with that same code.  Are we really
> 	gaining anything, or is it merely psychological?

Its its not for the sake of exectution efficiency.  You see it
a lot for the sake of statement efficiency.  Its the efficient and STANDARD
way of saying it.  Any experienced C programmer recognizes this code
automatically and produces it without thinking.  You have problems with
it because you are not an experienced C programmer yet.

You of course need to include the missint paren :-)