Subject: Re: Switching to ELF
To: Paulo Alexandre Pinto Pires <>
From: Ignatios Souvatzis <>
List: current-users
Date: 02/06/1999 21:08:46
On Fri, Feb 05, 1999 at 12:01:42AM -0200, Paulo Alexandre Pinto Pires wrote:
> Hello, all.
> Even though I don't understand enough of internals to know what makes
> ELF better than a.out, recent UNIX-like OSes migration towards it
> (besides development tools optimizations for ELF) makes me curious
> about changing my NetBSD boxes to use it.
> How safe, however, is it to switch a system which has already some
> useful things installed, which would take a long time be be set up
> again?  Is NetBSD's a.out to ELF transition less painful than
> FreeBSD's and Linux's (especially this) were?

Given that we already support having several executable types in a kernel
(EXEC_SCRIPT, and EXEC_AOUT, for example, on this machine I'm typing on)
it should be doable smoothly.

Just have both EXEC_AOUT and EXEC_ELF32 in your kernel during the transition
period. (Well, there might be additional requirements wrt. shared libraries,
but these will eventually be handled by the implementors.)