Re: Fwd: Re: fmtcheck() query

[Rin Okuyama <rokuyama%rk.phys.keio.ac.jp@localhost>]

On 2017/12/14 0:06, Valery Ushakov wrote:
> Christos Zoulas <christos%zoulas.com@localhost> wrote:
>
> > | Yes, I'm so sorry for this breakage of file(1). It clearly indicates
> > | possible risks of changing the behavior of fmtcheck(3).
> >
> > Thank you very much. I think that adding a new function is preferrable
> > in this case because we are adding significant new functionality (by the
> > positional arguments handling). We should leave the old fmtcheck(3) alone
> > (so that existing code does not break) and just document its deficiencies
> > and say to use fmtmatch(3) instead.
>
> If the new function provides a flag that controls whether unused
> trailing ares are ok, then fmtcheck() can be just a trivial wrapper.

I agree with this. fmtcheck(3) can be something like

const char *
fmtcheck(const char *s1, const char *s2)
{

	return fmtmatch(s1, s2, 0);
}

> One thing I sort of never figured out properly is convenient error
> reporting.  My current code uses a fixed-size buffer in the
> user-supplied struct, but asprintf(3) may be a better option.
>
> I think error messages are important here, as visually matching the
> rejected format and the template is a pain and is kidna stupid anwyay
> since the function already knows exactly what's wrong.

Sure, I'll try to implement it :-).

rin