Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!uunet!mcsun!hp4nl!and!jos
From: jos@and.nl (J. Horsmeier)
Newsgroups: comp.lang.c
Subject: Re: Bit Masking Question
Message-ID: <980@baby.and.nl>
Date: 24 Jun 91 10:56:08 GMT
References: <12191@hub.ucsb.edu>
Organization: AND Software BV Rotterdam
Lines: 44

In article <12191@hub.ucsb.edu> angst@cs.ucsb.edu (Hopelessly in love w/Donna Reed) writes:
>What I'm doing is reading characters from a file and I'd like to 
>categorise the characters into 3 groups based on their 2 most-
[...]
>
>    #define FMASK   0xC0
>    #define RMASK   0x80
>    int c;
>	    switch (c & FMASK) {
[ normal cases ...]
>		case 0x0:
>		case 0x40:
>		    Do stuff for group 3

		^^^^^^ Make this the default ...
>		    ...
>
>		default:
>		    fprintf (stderr, "bad news!\n");

		^^^^^^ this is the same kind of paranoia as:

		for (i= 0; i < 10; i++)
		   if (i >= 10) ZombyWoof();
>	    }
>
>This seems to work, but I'd like comments.  Is there a better way to
>do this?  Should I make #define's for 0x0 and 0x40?  Is there a way
>to #define bits?o

This is not really much of a problem is it? Your code works fine, 
it's compact, fast etc. It'll do the job :-)


Jos


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