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From: bruce@seismo.gps.caltech.edu (Bruce Worden)
Newsgroups: comp.lang.c
Subject: Re: more that 32 flag array testing
Keywords: boolean,testing,bits
Message-ID: <1990Oct9.175837.4582@nntp-server.caltech.edu>
Date: 9 Oct 90 17:58:37 GMT
References: <1990Oct8.165154.26747@vitro.uucp>
Sender: bruce@seismo.gps.caltech.edu (Bruce Worden)
Organization: California Institute of Technology, CA
Lines: 16
Nntp-Posting-Host: sis.gps.caltech.edu

In article <1990Oct8.165154.26747@vitro.uucp> fsb@vitro.uucp (Steve Brailsford) writes:
> [ looking for a way to set and test boolean flags ]

I don't know what you consider to be too computationally intensive, but you 
might want to look at the way the macros that support the "select()" function 
provide the exact (almost) functionality you are looking for.  Four macros 
(with some supporting code) are provided: FD_SET, FD_CLR, FD_ISSET, and 
FD_ZERO.  It should be a simple matter to modify them to work for any sized 
string of bits.  They are defined in <sys/types.h>.  Good luck.

(Note, the select() function itself is of no interest here, just the macros 
that support it.  If you don't have these macros, and you send my a working
e-mail address, I'll send you some non-copyright-infringing copies.)
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C. Bruce Worden                            bruce@seismo.gps.caltech.edu
252-21 Seismological Laboratory, Caltech, Pasadena, CA 91125