Re: [COMMITTERS] pgsql: Add comments about why errno is set

OK, comments removed, and comment added to port/strtol.c.

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Tom Lane wrote:
> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > I modified it to:
> >         errno = 0;  /* avoid having to check the result for failure */
> 
> Just for the record, that's *still* wrong.  It implies that if we
> tested (result == LONG_MAX && errno == ERANGE), without zeroing
> errno beforehand, the code would be correct.  But it would not,
> because the errno value could still be leftover.  The plain fact
> of the matter is that if you're going to check for strtol overflow at
> all, you have to zero errno beforehand.  This is perfectly well
> explained in the strtol spec page, and I see no need to duplicate it:
> 
>     Because 0, LONG_MIN and LONG_MAX are returned on error and are
>     also valid returns on success, an application wishing to check
>     for error situations should set errno to 0, then call strtol(),
>     then check errno.
> 
>             regards, tom lane
> 

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