Path: utzoo!attcan!uunet!peregrine!elroy!ames!mailrus!cornell!batcomputer!itsgw!imagine!rpics!kyriazis
From: kyriazis@rpics (George Kyriazis)
Newsgroups: comp.lang.c
Subject: Re: What does Z["ack"] = 5 mean?
Keywords: Obfuscated C, wierd
Message-ID: <1326@imagine.PAWL.RPI.EDU>
Date: 5 Oct 88 20:54:02 GMT
References: <14999@agate.BERKELEY.EDU>
Sender: news@imagine.PAWL.RPI.EDU
Reply-To: kyriazis@turing.cs.rpi.edu (George Kyriazis)
Organization: RPI CS Dept.
Lines: 25

In article <14999@agate.BERKELEY.EDU> laba-3aw@web.berkeley.edu (Sam Shen) writes:
>Exactly what does this mean:
>
>main()
>{
>	char Z;
>
>	Z["ack!"] = 5;
>}
>

	Something like that was posted a few months ago.  Remember that

		a[b]  == *(a+b)		[pointer erithmetic]
		*(a+b) == *(b+a)	[obvious]
		*(b+a) == b[a]		[!!!!]

	In other words  Z["ack!"] == "ack!"[Z]  (!!). Z happens to be '\0',
so what is does is changes the first character of the constant "ack!" to 5.
In some systems you can't do that because constants are read-only.  I just
tried it on a SUN4 and it didn't complain at all..

  George Kyriazis
  kyriazis@turing.cs.rpi.edu
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