Re: Extent of the "as-if" rule

From: pete (pfiland_at_mindspring.com)
Date: 01/30/04 

Date: Fri, 30 Jan 2004 17:36:18 GMT

Douglas A. Gwyn wrote:
>
> Dan Pop wrote:
> > Nope: such programs invoke undefined behaviour,
> > so they cannot be used in testing the conformance.
> > Even if this weren't the case, the action
> > in question could be performed 1e6 years after
> > the program startup...
>
> Your "logic" leads to the conclusion that conformance
> testing is impossible. Fortunately, you are wrong.

I believe that the claim, "Excedes ANSI Specifications",
is already in use. I always interpreted it to mean that the
compiler did not self destruct after translating one program.

And now if I may change change the topic to some old business:

Is it legitimate for a function like puts,
to return at the first sign of EOF, like this:

int puts(const char *s)
{
    while (*s != '\0') {
        if (putchar(*s) == EOF) {
            return EOF;
        }
        ++s;
    }
    return putchar('\n');
}

or must it keep hammering away, regardless of EOF, like this:

int puts(const char *s)
{
    int eof = 0;

    while (*s != '\0') {
        if (putchar(*s) == EOF) {
            eof = 1;
        }
        ++s;
    }
    return putchar('\n') == EOF || eof != 0 ? EOF : 1;
}

? 

-- 
pete

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