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To: cs551@merlot.usc.edu
Subject: Re: CS-551 warmup-1
Date: Fri, 05 Sep 2008 13:16:39 -0700
From: Bill Cheng <william@bourbon.usc.edu>

Someone wrote:

  > So thats when we might get a seg fault or a bus error.

Sure!  If you have something like:

    unsigned char *buf=NULL;
    unsigned short msg_type=0xfe01;

    memcpy(buf, &msg_type, 2);

You should get a seg fault because you cannot copy to
memory locaiont 0.
--
Bill Cheng // bill.cheng@usc.edu <URL:http://merlot.usc.edu/william/usc/>





On Fri, Sep 5, 2008 at 5:58 AM, Bill Cheng <william@bourbon.usc.edu> wrote:

> Someone wrote:
>
>  > Does memcpy always work? I mean it does not have any return value, and
> the
>  > man pages do not specify anything on this too.
>
> The man pages say that it returns the first argument to it.
> So, I guess it "always works", except when you write into bad
> memory and get a SIGSEGV or SIGBUS.
> --
> Bill Cheng // bill.cheng@usc.edu <URL:http://merlot.usc.edu/william/usc/>
>
>