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From: guy@gorodish.UUCP
Newsgroups: comp.lang.c,comp.unix.wizards
Subject: Re: pointer alignment when int != char *
Message-ID: <26910@sun.uucp>
Date: Mon, 31-Aug-87 16:10:38 EDT
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Posted: Mon Aug 31 16:10:38 1987
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Xref: utgpu comp.lang.c:3902 comp.unix.wizards:3721

> However, I will say this, because I don't think the standard has really
> addressed it:  there should be a way to take any pointer and generate a byte
> offset from byte 0 in whatever address space the code is running in.  The
> reason is that you need such a beast to feed to lseek if you want to access
> something through one of the /dev/mem devices (or maybe /proc).

The standard should NOT address this.  The standard mentions neither "lseek"
nor "/dev/mem" nor "/proc".  This sort of thing is rather non-portable, and is
as such completely outside the scope of the standard.  Since getting at some
other address space must be done in a different fashion on different
implementations, it is perfectly OK to require that getting the location in
that other address space also be done in a different fashion on different
implementations.
	Guy Harris
	{ihnp4, decvax, seismo, decwrl, ...}!sun!guy
	guy@sun.com