From: utzoo!decvax!cca!perry.gatech@Udel-Relay@sri-unix
Newsgroups: net.unix-wizards
Title: Re:  Information on Unix/Vax peculiarities
Article-I.D.: sri-unix.4784
Posted: Fri Dec 10 04:35:49 1982
Received: Sat Dec 11 01:29:32 1982

From:     Perry Flinn <perry.gatech@Udel-Relay>
Date:     6 Dec 82 10:58:42-EST (Mon)
The following is quoted (without permission) from Kernighan and Ritchie
(sec. 14.4, pp. 210):

	A pointer may be converted to any of the integral types large
	enough to hold it.  Whether an int or long is required is
	machine dependent, but is intended to be unsurprising to those
	who know the addressing structure of the machine. ...

	An object of integral type may be explicitly converted to a
	pointer.  The mapping always carries an integer converted from
	a pointer back to the same pointer, but is otherwise machine
	dependent.

	A pointer to one type may be converted to a pointer to another
	type.  The resulting pointer may cause addressing exceptions
	upon use if the subject pointer does not refer to an object
	suitably aligned in storage.  It is guaranteed that a pointer
	to an object of a given size may be converted to a pointer to
	an object of smaller size and back again without change.

--Perry