From owner-freebsd-questions Wed Mar 24 11:30:40 1999 Delivered-To: freebsd-questions@freebsd.org Received: from comton.airs.com (comton.airs.com [199.103.241.106]) by hub.freebsd.org (Postfix) with SMTP id 7CF7415458 for ; Wed, 24 Mar 1999 11:30:36 -0800 (PST) (envelope-from ian@airs.com) Received: (qmail 8036 invoked by uid 269); 24 Mar 1999 19:30:14 -0000 Message-ID: <19990324193014.8035.qmail@comton.airs.com> From: Ian Lance Taylor Date: 24 Mar 1999 14:30:14 -0500 To: patl@phoenix.volant.org Cc: freebsd-questions@freebsd.org In-reply-to: Subject: Re: FreeBSD FAQ and a.out Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Date: Wed, 24 Mar 1999 10:02:59 -0800 (PST) From: patl@phoenix.volant.org > We did encourage people to move to ELF, because it is better. It > supports multiple sections, permits the alignment of those sections to > be set individually, and it provides shared library support that is as > good as SunOS and is easier to understand. ... It is as good or better except for one thing. It doesn't support minor revision numbers on libraries. I know this can be something of a religious issue; but I still believe that their advantages outweigh any percieved shortcommings. (And I do believe that the transition to ELF was, overall, a good thing.) The traditional approach is to use symlinks on the libraries, along with an appropriate SONAME. For a minor version enhancement, you can replace the shared library as a whole, although it's true that you can't simultaneously have some executables which require a particular minor version and some which don't. Note that the current GNU tools support a fairly sophisticated shared library versioning mechanism, based on one developed at Sun. This scheme permits a particular symbol or set of symbols to be changed within a shared library, without disturbing the behaviour of old programs. Ian To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message