From owner-cvs-src@FreeBSD.ORG Sun Sep 5 19:46:34 2004 Return-Path: Delivered-To: cvs-src@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 490CF16A4CE; Sun, 5 Sep 2004 19:46:34 +0000 (GMT) Received: from cs.rice.edu (cs.rice.edu [128.42.1.30]) by mx1.FreeBSD.org (Postfix) with ESMTP id 074D343D49; Sun, 5 Sep 2004 19:46:34 +0000 (GMT) (envelope-from alc@cs.rice.edu) Received: from localhost (calypso.cs.rice.edu [128.42.1.127]) by cs.rice.edu (Postfix) with ESMTP id 751284A9F2; Sun, 5 Sep 2004 14:46:33 -0500 (CDT) Received: from cs.rice.edu ([128.42.1.30]) by localhost (calypso.cs.rice.edu [128.42.1.127]) (amavisd-new, port 10024) with LMTP id 11950-01-7; Sun, 5 Sep 2004 14:46:33 -0500 (CDT) Received: by cs.rice.edu (Postfix, from userid 19572) id 209FE4A9F0; Sun, 5 Sep 2004 14:46:33 -0500 (CDT) Date: Sun, 5 Sep 2004 14:46:32 -0500 From: Alan Cox To: Peter Pentchev , src-committers@FreeBSD.ORG, cvs-src@FreeBSD.ORG, cvs-all@FreeBSD.ORG Message-ID: <20040905194632.GK10220@cs.rice.edu> References: <200409030624.i836OPaL018916@repoman.freebsd.org> <20040905013043.GA29649@VARK.homeunix.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040905013043.GA29649@VARK.homeunix.com> User-Agent: Mutt/1.4.2i X-Virus-Scanned: by amavis-20030616-p7 at cs.rice.edu Subject: Re: cvs commit: src/lib/libc/sys msync.2 X-BeenThere: cvs-src@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: CVS commit messages for the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 05 Sep 2004 19:46:34 -0000 On Sat, Sep 04, 2004 at 09:30:43PM -0400, David Schultz wrote: > On Fri, Sep 03, 2004, Peter Pentchev wrote: > > roam 2004-09-03 06:24:25 UTC > > > > FreeBSD src repository (doc,ports committer) > > > > Modified files: > > lib/libc/sys msync.2 > > Log: > > Add a BUGS section and copy the wording from mmap(2)'s MAP_NOSYNC, > > documenting the obsoleteness of the msync(2) syscall and its single > > remaining purpose. > > I'm not nitpicking at you since you didn't write the original > text, but if msync(2) still has a purpose, then it isn't really > obsolete, is it? (Moreover, the text only describes the purpose of > msync(2) with the MS_ASYNC flag.) Applications such as databases > that want greater control over the flushing of dirty data may > still find msync(2) very useful. I agree. This sentence should be removed from both msync.2 and mmap.2 for precisely the reason you state. It is, however, worth mentioning that FreeBSD has a unified buffer and virtual memory page cache in these man pages. In fact, that does make most uses of msync()'s MS_INVALIDATE flag unnecessary. (The useful cases being things like the extension used by the Nvidia driver.) On a related note, where do we stand with respect to the use of X/Open man pages? The X/Open man page for msync(2) is much better than ours. Alan