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Date: Wed, 26 Jan 2005 11:13:34 +0100
From: Stefan Farfeleder <stefan@fafoe.narf.at>
To: keramida@ceid.upatras.gr
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cc: nectar@FreeBSD.org
cc: freebsd-bugs@FreeBSD.org
cc: sos22@cantab.net
Subject: Re: Dubious #define in include/pwd.h
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Giorgos Keramidas wrote:
> On 2005-01-25 21:46, Steven Smith <sos22 at cantab.net> wrote:
> > I was messing around with sparse, the static checker used sometimes
> > by Linux kernel people, and I (or rather, it) came upon the line
> >
> > #define _PW_VERSION_MASK        '0xF0'
> >
> > in /usr/src/include/pwd.h.  I can't immediately see any use for this;
> > '\xf0' would probably be more useful.
> 
> If this is used as a mask for 'unsigned char' values, why would it make
> any difference?  Aren't they both going to be implicitly converted to
> the right typep anyway?

No, '0xF0' is a multi-character-constant, its value is implementation-defined
and that's probably not what Jacques (CC'ed) intended.  It probably
should be just 0xF0 (without the quotes) or '\xF0'.  A grep through the
src tree didn't show any usage of this macro though.

Stefan