Path: utzoo!attcan!uunet!indetech!schmidt
From: schmidt@indetech.com (Doug Schmidt)
Newsgroups: comp.lang.c
Subject: validity of free() on later pointer operations
Message-ID: <1990Jul3.185032.8434@indetech.com>
Date: 3 Jul 90 18:50:32 GMT
Reply-To: schmidt@indetech.UUCP (Doug Schmidt)
Organization: Independence Technologies, Inc. Fremont, CA
Lines: 34


Hi,

	Several months ago there was a big discussion on comp.lang.c
about the legality/portability of the following sort of code:

----------------------------------------
void
foo (n)
	int n;
{
	char *malloc ();

	char *s = malloc (n);
	/* ... */
	free (s);
	s = 0; /* Is this assignment always legal? */
	/* ... */
}
----------------------------------------

	I seem to recall there was a problem with the assignment to
char *s *after* the free.  Can someone please refresh my memory
as to what the problem was, and why it is a problem?  Would
replacing s = 0 by s = malloc (n) have the same problem?

	thanks,
	
		Doug
-- 
____*_  Douglas C. Schmidt          schmidt@indetech.com
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