Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!tut.cis.ohio-state.edu!ucbvax!SCT60A.SUNYCT.EDU!sweetmr
From: sweetmr@SCT60A.SUNYCT.EDU (michael sweet)
Newsgroups: comp.sys.sgi
Subject: Re: realloc()....
Message-ID: <9102170140.AA09389@sct60a.sunyct.edu>
Date: 17 Feb 91 01:40:25 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 26


> ... how come calling realloc() with a NULL pointer bombs....

Well, that's one of those nice functions which was never standardized for
that sort of thing- *most* libraries do take a NULL pointer happily, but
then some don't.  Both K&R 1 and 2 fail to say anything on how to deal with
NULL pointers and realloc() :(

One easy way around it is to use a macro like:

 #define REALLOC(p,n)  ((p) ? realloc((p),(n)) : malloc((n)))

(The extra parens are needed for old compilers)

In any case, this adds some safety at the expense of a few bytes of code;
this is also something that could be #ifdef'd for brain-dead systems so
smart systems don't suffer the overhead....

 -Mike Sweet

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