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From: flee@shire.cs.psu.edu (Felix Lee)
Newsgroups: comp.lang.c
Subject: Re: Another pitfall.  Signed chars and ctype.h.
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Date: 10 Feb 90 02:27:28 GMT
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John Woods <john@frog.UUCP> wrote:
> You have to say
>	isascii(*s) && isdigit(*s)

According to _Standard C_ by Plauger and Brodie (the best reference I
have), there is no "isascii".  And "isdigit" etc. take an int in the
set (EOF, 0..UCHAR_MAX), e.g., the possible return values of fgetc().

So, to write ANSI conformant C you must always say something like
	isdigit((unsigned char) *s)
--
Felix Lee	flee@shire.cs.psu.edu	*!psuvax1!flee