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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: How to compile several C files
Date: Wed, 08 Feb 2017 09:27:46 -0800
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David Brown <david.brown@hesbynett.no> writes:
[...]
> What you can do, and I have done, is something like:
>
> 	// In one C file
> 	int counter_private;
>
> 	// In header file
> 	extern int counter_private;	// Do not use!
> 	#define counter ((const int) counter_private)

Note that the const in the cast is probably useful as documentation, but
it's not really necessary, since a cast expression is not an lvalue.

You could also have:

    #define counter (+counter_private)

[...]

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"