Path: utzoo!attcan!uunet!jarthur!usc!ucsd!ucbvax!BBN.COM!pmorris
From: pmorris@BBN.COM (Phil Morris)
Newsgroups: comp.society.futures
Subject: Re: C's sins of commission (was: (pssst...fortran?))
Message-ID: <9009202211.AA15218@encore.encore.com>
Date: 20 Sep 90 22:16:20 GMT
References: <9009202104.AA21146@raven.pa.dec.com>
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 48

>Date: Thu, 20 Sep 90 14:04:29 PDT
>From: Mike Meyer <mwm@decwrl.dec.com>
>Subject: Re: C's sins of commission (was: (pssst...fortran?))
>To: jlg@lanl.gov
>Cc: info-futures@encore.com

[...]

>You've as yet to answer my questions about garbage collection, and
>what constructs would be provided for working with sequences. As an
>addendum to that list, I'd be interested to know how you would recode
>the following C sequence with undefined behavior using your proposed
>constructs so that it would do what it's author intended:
>
>	long 	word ;
>	char	*pointer ;
>
>	word = '1234' ;
>	pointer = (char *) word ;
>	printf("%c %c %c %c\n", pointer++, pointer++, pointer++, pointer++) ;
>
>The intent was to determine the byte ordering of the machine the code was
>running on.
>
>	<mike

How about something as simple as:

#define SZLONG sizeof(long)

	union xxx {
		long word;
		char str[SZLONG];
	} un;

	un.word = '1234';
	printf("%c %c %c %c\n", un.str[0], un.str[1], un.str[2], un.str[3]);


It works on my machine, and the hypothetical language under discussion can handle these
constructs (except he didn't mention how to do sizeof(xxx)).

-Phil


--------
Phil Morris (pmorris@dgi0.bbn.com)
Disclaimer: ME? I'm only a non-smoking cat; can't believe a word I meow.