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From: ee161aba@sdcc18.ucsd.EDU (David L. Smith)
Newsgroups: comp.lang.c++
Subject: Passing pointers by reference
Message-ID: <572@sdcc18.ucsd.EDU>
Date: Mon, 1-Dec-86 04:05:28 EST
Article-I.D.: sdcc18.572
Posted: Mon Dec  1 04:05:28 1986
Date-Received: Mon, 1-Dec-86 08:44:40 EST
Organization: University of California, San Diego
Lines: 27


Is it possible to call a function with a pointer by reference?  What I am
trying to do is pass a pointer and I want to be able to modify the pointer
value (not what it points to).  Logically, something like:

	foo(bar & * junk) 

should do it. This would be a pointer to bar passed by reference to the
function foo.  However, this does not work.  I attempted to fool the
pre-processor by doing:

class bar {
	typdef bar *bar_p;
	foo(bar_p & junk)
}

This fools the pre-processor, but the code it produces chokes the C compiler.
Specifically, it omits the typedef for bar_p and attempts to use it anyhow 
without any kind of definition anywhere.

I realize I could use a double indirected pointer (and I probably will end
up doing so) but I'm lazy and the call by reference is an elegant mechanism.
Now if only it would work!

			David L. Smith
			UC San Diego
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