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From: mikey@ontek.com (michelle (krill-woman) lee)
Newsgroups: comp.lang.c
Subject: Re: Why 'life after free'.
Message-ID: <1384@ontek.com>
Date: 5 Oct 90 00:51:34 GMT
References: <1990Sep30.163824.12974@ibmpcug.co.uk> <1990Oct2.104509.1744@funet.fi>
Followup-To: emptiness
Organization: Ontek Corporation -- Laguna Hills, California
Lines: 27

| > char *
| > funny(c)
| > char c;
| > {
| > 	static char a[100];
| > 	int i;
| > 
| > 	for (i=0 ; i<99 ; i++) a[i] = c;
| > 	a[99] = '\0';
| > 	return (&a[0]);
| > }
| > 
| 
| 	With this function call's like
| 	printf( "%s %s\n", funny( 'x' ), funny( 'y' ) );
| 	do not work as expected.

      This sort of thing wouldn't work with malloc/free as originally
proposed either.  If funny freed the block its return pointer pointed 
at,  the second invocation (not necessarily the one for y, btw) might 
cause malloc to stomp on the thing that was just freed, before printf
even has a chance to print it.  It's either that or don't free it and 
get a memory leak.  Better solutions have been mentioned elsewhere in
this thread of articles,  i.e. using variables in the caller to store
the result.

the krill, i/o bound