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From: David Emery <demery@cox.net>
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Subject: Re: of possible interest
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Date: Thu, 11 May 2006 18:25:32 -0400
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Date: 2006-05-11T18:25:32-04:00
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There's a lot of anecdotal and probably some documented evidence on large chunks of C code where the return value of a system call was ignored.  Those 2 ATT/Bell Labs studies on common programming errors in C on the 5ESS project documented this as a problem (if I remember correctly) and recommended some solutions (but not the right one, switching to a language with exceptions and where at least syntactically, you had to provide a container for a function return, even if you ignore the result... :-). 

A good compiler should issue a warning in the following situation:

declare
	return_value : error_status_codes;
begin
	return_value := some_function (parameters);
	do_more_computations (parameters);
end;

noting that "return_value" is never used.  That's usually a hint of a problem.

    dave