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From: chris@mimsy.UUCP (Chris Torek)
Newsgroups: comp.lang.c
Subject: Re: Varargs problem
Message-ID: <19271@mimsy.UUCP>
Date: 26 Aug 89 00:04:09 GMT
References: <4YxPuc200VsnE_B3Jy@andrew.cmu.edu>
Organization: U of Maryland, Dept. of Computer Science, Coll. Pk., MD 20742
Lines: 21

In article <4YxPuc200VsnE_B3Jy@andrew.cmu.edu> bobg+@andrew.cmu.edu
(Robert Steven Glickstein) writes:
>I wish to extract a variable of type "pointer to function returning int"
>[(int (*) ())] from a varargs parameter list, and I can't.
>        fn = va_arg(ap, int (*) ());

va_arg must be handed a type that can legally have one `*' added on the
end; int (*)() is not such a type.

The solution is to create a typedef:

	typedef int (*intfn_t)();
	...
	fn = va_arg(ap, intfn_t);

With one small change (`typedef int (*intfn_t)(void)') one gets an ANSI-
style extraction.  (Alas, the `va_start' invocations and function
declarations must be changed.)
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci Dept (+1 301 454 7163)
Domain:	chris@mimsy.umd.edu	Path:	uunet!mimsy!chris