From owner-freebsd-emulation Mon Dec 28 14:07:59 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id OAA29713 for freebsd-emulation-outgoing; Mon, 28 Dec 1998 14:07:59 -0800 (PST) (envelope-from owner-freebsd-emulation@FreeBSD.ORG) Received: from janus.syracuse.net (janus.syracuse.net [205.232.47.15]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id OAA29698 for ; Mon, 28 Dec 1998 14:07:55 -0800 (PST) (envelope-from green@unixhelp.org) Received: from localhost (green@localhost) by janus.syracuse.net (8.8.8/8.8.7) with ESMTP id RAA03339; Mon, 28 Dec 1998 17:07:25 -0500 (EST) Date: Mon, 28 Dec 1998 17:07:25 -0500 (EST) From: Brian Feldman X-Sender: green@janus.syracuse.net To: "Richard Seaman, Jr." cc: Mike Smith , emulation@FreeBSD.ORG Subject: Re: StarOffice 5.0? In-Reply-To: <19981228155821.C4581@tar.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-emulation@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Mon, 28 Dec 1998, Richard Seaman, Jr. wrote: > On Mon, Dec 28, 1998 at 04:50:08PM -0500, Brian Feldman wrote: > > > > This looks ominously like the linux_pipe patches have been spammed by > > > something else. > > > > I see nothing referring to p->p_md.md_regs->tf_edx, so I see no reason why it > > should have been saved. > > > > int reg_edx; > > reg_edx = p->p_retval[1]; > > p->p_retval[1] = reg_edx; > > p->p_retval[1] = reg_edx; > > It's saving the value, but what's it got to do with edx? > > p->p_retval[1] writes to edx when returning to user space. The > FreeBSD pipe syscall writes to p->p_retval[1]. Linux glibc wraps > the linux pipe syscall, and expects edx to be preserved when the > pipe syscall returns. > Okay, that makes sense. Where is it noted what FreeBSD clobbers and what it restores on leaving a syscall? And is it really a good thing? I mean, should I expect all my registers to be exactly the same (well, I mean the generic storage registers, not esp eip etc ;) on return of a syscall? > -- > Richard Seamman, Jr. email: dick@tar.com > 5182 N. Maple Lane phone: 414-367-5450 > Chenequa WI 53058 fax: 414-367-5852 > Brian Feldman _ __ ___ ___ ___ green@unixhelp.org _ __ ___ | _ ) __| \ http://www.freebsd.org/ _ __ ___ ____ | _ \__ \ |) | FreeBSD: The Power to Serve! _ __ ___ ____ _____ |___/___/___/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-emulation" in the body of the message