Newsgroups: comp.os.minix
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: Where is isascii(c)?
Message-ID: <1990Feb1.172916.16504@utzoo.uucp>
Organization: U of Toronto Zoology
References: <589@loft386.UUCP> <592@loft386.UUCP> <23330@princeton.Princeton.EDU> <2289@psueea.UUCP> <596@loft386.UUCP> <2300@psueea.UUCP> <5257@star.cs.vu.nl>
Date: Thu, 1 Feb 90 17:29:16 GMT

In article <5257@star.cs.vu.nl> ast@cs.vu.nl (Andy Tanenbaum) writes:
>If ANSI requires the range 0-255, I'll do it.  What section of the draft
>standard specifies that one has to handle 128-255?  What values should
>one put in the table above 127?  All 0s?

The intro to 4.3 says the values of the isxxx functions are defined on
all values representable as "unsigned char", plus EOF.  Unless you've
done something very strange to the compiler :-), unsigned char is 0-255.

How you set the values for the high characters is a good question.  All
zeros appears to be legitimate, and might be the simplest thing.  (I'm
tempted to say that the values should follow ISO Latin 1, but that's
asking for trouble since lots of hardware isn't set up to deal with
ISO Latin 1 yet.)
-- 
1972: Saturn V #15 flight-ready|     Henry Spencer at U of Toronto Zoology
1990: birds nesting in engines | uunet!attcan!utzoo!henry henry@zoo.toronto.edu