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From: lewine@dg-rtp.dg.com (Donald Lewine)
Newsgroups: comp.std.c
Subject: Re: Floating point output
Message-ID: <876@dg.dg.com>
Date: 30 Aug 90 17:12:10 GMT
References: <3295@skye.ed.ac.uk>
Sender: root@dg.dg.com
Reply-To: uunet!dg!lewine
Organization: Data General Corporation
Lines: 30

In article <3295@skye.ed.ac.uk>, jeff@aiai.ed.ac.uk (Jeff Dalton) writes:
|> In May 13 1988 draft (sorry, it's the only one I have), X3J11/88-90,
|> it says:
|> 
|>    A strictly conforming program ... shall not produce output
|>    dependent on any unspecified, undefined, or implementation-
|>    defined behavior.  [Section 1.7, page 4]
|> 
|> Since the representations of floating types are unspecified,
|> what, if any, output of fp numbers is allowed in strictly
|> conforming programs?

Section 4.9.6.1 describes the fprintf() conversions for %f, %e, %E,
%g and %G.  They produce well defined output.

NOTE: It is possible to have a strictly conforming application which
	  produces machine specific, non-portable output.  If your 
	  program writes an array of double out with fwrite() and reads
	  it back with fread(), the program may be conforming and 
	  portable even though the data is machine specific.

	  This file is not an "output" of the program. 

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