NetNews Offline 2/NetNews Offline Volume 2.iso/news/comp/lang/c-part1/4417

Internet Message Format | 1996-08-05 | 1.7 KB

Path: Rezonet.net!news
From: [e-mail] (Ray Dunn)
Newsgroups: comp.lang.c
Subject: Re: Recursive function -> how do you exit one?
Date: 2 Feb 1996 18:38:32 GMT
Organization: Ultimate Technographics Inc.
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In referenced article, Steve Tupy says...
>: You need to return a value which makes all the recursed functions
>: exit without further processing.
>
>: if the function returns an int then you could return -1 as aborted.
>: if it returns a char or char* you can use a (first) character that
>: cannot exist in your string. eg 0xff
>
>: char* foo()
>: {
>:    result=foo();
>:    if(*result!=0xff)
>:    {
>:       // process things here //
>:       if (aborted) return "\xff";
>:    }
>:    return result;
>: }
>
>: Does that help?
>
>        What is result, an int? Where is it defined? Don't you agree
>that it should also be static? If not, you might find that its value
>gets lost on the stack, especially when you are unwinding the stack
>during a recursive call...

The declaration of result has certainly been ommitted here, and because
it is getting the result of foo(), it should be a  char *;  A more
natural thing to return in the aborted state would be NULL.

But in any case, there is absolutely no need for result to be static,
as on every return, result is being reupdated with the current result
of foo.

--
Ray Dunn (opinions are my own) | Phone: [phone]
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