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From: brnstnd@kramden.acf.nyu.edu (Dan Bernstein)
Newsgroups: comp.lang.c
Subject: Re: memory management between functions
Message-ID: <6394:Apr2915:34:0991@kramden.acf.nyu.edu>
Date: 29 Apr 91 15:34:09 GMT
References: <8504@umd5.umd.edu>
Distribution: na
Organization: IR
Lines: 12

In article <8504@umd5.umd.edu> jjk@astro.umde.edu (Jim Klavetter) writes:
> for(i=0; i<n; i++)
> 	c[i]=a[i]-b[i];
> free(c);
> return(c);

A pointer is just an address. The pointer variable c holds the address
of a malloc'ed array. When you blow away the array, c's address is out
of date, and once the array elements are dead and buried the postmaster
can't forward your mail (c[i]) to the cemetery.

---Dan