From owner-freebsd-hackers Tue Aug 24 2:45:21 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from allegro.lemis.com (allegro.lemis.com [192.109.197.134]) by hub.freebsd.org (Postfix) with ESMTP id 8E7A4158A9 for ; Tue, 24 Aug 1999 02:44:39 -0700 (PDT) (envelope-from grog@freebie.lemis.com) Received: from freebie.lemis.com (freebie.lemis.com [192.109.197.137]) by allegro.lemis.com (8.9.1/8.9.0) with ESMTP id TAA24207; Tue, 24 Aug 1999 19:13:36 +0930 (CST) Received: (from grog@localhost) by freebie.lemis.com (8.9.3/8.9.0) id TAA93456; Tue, 24 Aug 1999 19:13:36 +0930 (CST) Date: Tue, 24 Aug 1999 19:13:36 +0930 From: Greg Lehey To: Ville-Pertti Keinonen Cc: John-Mark Gurney , hackers@freebsd.org Subject: Re: Mandatory locking? Message-ID: <19990824191335.O83273@freebie.lemis.com> References: <19990823223645.A14001@netmonger.net> <19990824021431.55023@hydrogen.fircrest.net> <86pv0djz6o.fsf@not.demophon.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.95.4i In-Reply-To: <86pv0djz6o.fsf@not.demophon.com>; from Ville-Pertti Keinonen on Tue, Aug 24, 1999 at 12:38:38PM +0300 WWW-Home-Page: http://www.lemis.com/~grog X-PGP-Fingerprint: 6B 7B C3 8C 61 CD 54 AF 13 24 52 F8 6D A4 95 EF Organization: LEMIS, PO Box 460, Echunga SA 5153, Australia Phone: +61-8-8388-8286 Fax: +61-8-8388-8725 Mobile: +61-41-739-7062 Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Tuesday, 24 August 1999 at 12:38:38 +0300, Ville-Pertti Keinonen wrote: > > gurney_j@efn.org (John-Mark Gurney) writes: > >> Ville-Pertti Keinonen scribbled this message on Aug 24: > >>> cat writes part of oldmail to /var/mail/grog >>> sendmail locks /var/mail/grog >>> (cat may try to write more to /var/mail/grog but blocks) >>> sendmail delivers new mail >>> sendmail unlocks /var/mail/grog >>> cat writes the rest of oldmail to /var/mail/grog >>> >>> You'll still probably end up with a broken mailbox. >> >> what you do is this: >> lockf -k $mailfile cat ${mailtmp} >> $mailfile > > Which doesn't support Greg's arguments for mandatory locking, as > you're now doing locking in both programs. Well, it doesn't support the last argument I made, which was untenable. It doesn't affect most of the others. And we're some distance from the dreaded deadlocks. Greg -- See complete headers for address, home page and phone numbers finger grog@lemis.com for PGP public key To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message