Subject: Re: ancillary data alignment and binary backward compatibility
To: Chris G. Demetriou <firstname.lastname@example.org, email@example.com>
From: Matt Thomas <firstname.lastname@example.org>
Date: 03/08/2000 15:22:20
At 01:19 PM 3/8/00 , email@example.com wrote:
> hmm, it seems I was wrong about the choice... does the following
> look like the right way?
> - change syscall # of sendmsg and recvmsg.
> - add ALIGNBYTES to syscall argument for sendmsg/recvmsg. it will be
> added by syscall library (it means that, at least, libc and
> user code must agree about ALIGNBYTES).
> for old syscall #, ALIGNBYTES arg will be hardcoded into 3 at
> kernel entry point.
> - propagate alignment constraint value given from the userland into all
> over the places like sys/netinet6, sys/netiso or sys/netccitt.
> there's some incompatibility window for several weeks (with my
> change that uses hw.alignbytes).
NO! Leave things as they are. The compat/netbsd32 code will need to re-layout
any control data before passing to/from the user and native socket layer.
Matt Thomas Internet: firstname.lastname@example.org
3am Software Foundry WWW URL: http://www.3am-software.com/bio/matt/
Cupertino, CA Disclaimer: I avow all knowledge of this message