Re: /usr/bin/printf: invalid universal character name

[Hermann Peifer]

Jim Meyering <address@hidden> wrote:
> Bruno Haible <address@hidden> wrote:
> > Jim Meyering wrote:
> >> Paul Eggert added this feature 8 years ago
> >
> > Well, all honours to Paul, but this feature I did submit to you on
> 2000-02-02.
> 
> Oh!  Sorry to misattribute that.
> I looked at the wrong ChangeLog entry.
> 
> >> I don't know the motivation for those exceptions.
> >
> > The motivation is that the ISO C 99 standard has these exceptions:
> >
> >   ISO C 99, 6.4.3(2):
> >   "Constraints
> >    A universal character name shall not specify a character whose short
> >    identifier is less than 00A0 other than 0024 ($), 0040 (@), or 0060
> (`),
> >    nor one in the range D800 through DFFF inclusive."
> >
> > and I find it undesirable to have different variants of the same concept
> in
> ...
> Thanks for explaining.
> 
> > You are entitled to your opinion. So that you cannot call it "bugs" any
> more,
> > I propose to make the restriction explicit in the coreutils manual:
> >

OK. Fine. I am ready to change my opinion and regard the issue as a feature, 
rather than a bug.

I only have a simple user perspective and don't know much about C 99. I was 
only wondering:

Why does /usr/bin/printf "\x41\n" print 'A' and  /usr/bin/printf "\u0041\n" 
reports: 'invalid universal character name \u0041'

Many thanks for your time and all explanations, Hermann