Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!udel!haven!adm!smoke!gwyn
From: gwyn@smoke.brl.mil (Doug Gwyn)
Newsgroups: comp.lang.c
Subject: Re: Question about using void *
Message-ID: <14902@smoke.brl.mil>
Date: 20 Jan 91 08:20:39 GMT
References: <1991Jan18.225308.25139@Solbourne.COM>
Organization: U.S. Army Ballistic Research Laboratory, APG, MD.
Lines: 13

In article <1991Jan18.225308.25139@Solbourne.COM> imp@Solbourne.COM (Warner Losh) writes:
>My question is: Is this portable?  Can I stuff an integer into a
>pointer and expect to get it back out again?

Any use of void* is not going to work on some pre-ANSI compilers.

It is not generally safe to try to convert an arbitary integral
value to a pointer.  While the implementation much provide SOME
integral type capable of holding a (properly converted) object
pointer, the converse is not required.  (Only for values
obtained by starting with a valid pointer.)

This is an ideal place to use a union type.