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Re: using the interfaces in ctype.h
On Sun, 20 Apr 2008, Greg A. Woods; Planix, Inc. wrote:
> Indeed! Some implementations were so lame they didn't include the
> mask in the implementation of the macro!
If the implementation masked the value before using it, then it would be
unable to distinguish EOF from UCHAR_MAX (typically '\377'). Anyway,
the onus falls on the caller to ensure that they don't pass invalid
values; otherwise the implementation is allowed to do anything at all.
> Oh oh, oops, the NetBSD implementations don't seem to include the mask
> either! I didn't realized that! So sad. (Which may even mean they
> violate the standards implication that they be able to safely accept
> the value of EOF.
Huh? The NETBSD implementations accept EOF. Since masking inside the
implementation would violate the requirement to distinguish EOF from
UCHAR_MAX, it's good that NetBSD doesn't do that.
think that masking inside the implementation would be
> FreeBSD, OpenBSD, and Darwin all seem to have much better
> implementations, though they are all using proper (inline) functions
> which makes it easier in some ways to do it right.)
I am mildly curious. In what way are they "better"?
--apb (Alan Barrett)
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