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From: jik@athena.mit.edu (Jonathan I. Kamens)
Newsgroups: comp.lang.c
Subject: Re: realloc() (was: Re: Safe coding practices)
Message-ID: <1991Jan30.193308.3897@athena.mit.edu>
Date: 30 Jan 91 19:33:08 GMT
References: <23975:Jan2516:36:5891@kramden.acf.nyu.edu> <1991Jan30.121425.16882@unhd.unh.edu>
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In article <1991Jan30.121425.16882@unhd.unh.edu>, pas@unhd.unh.edu (Paul A. Sand) writes:
|> Emphasis is Jaeschke's. Even a tyro like me can recognize that you
|> are in big trouble if (a) the realloc() fails, (b) ptr is your only
|> access to the block, and (c) you had something important there.

  I believe that if the realloc() fails, the memory block pointed to by the
pointer passed into realloc() is no longer guaranteed to be valid.  Therefore,
Jaeschke is right -- after realloc() returns NULL, you should not try to use
the block whose address you passed into realloc().


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