Mailing-List: contact cygwin-help@cygwin.com; run by ezmlm List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner@cygwin.com Mail-Followup-To: cygwin@cygwin.com Delivered-To: mailing list cygwin@cygwin.com Date: Sat, 28 Aug 2004 11:14:42 +0200 From: Corinna Vinschen To: cygwin@cygwin.com Subject: Re: F_ULOCK, F_LOCK, F_TLOCK, F_TEST missing in unistd.h Message-ID: <20040828091442.GD4786@cygbert.vinschen.de> Reply-To: cygwin@cygwin.com Mail-Followup-To: cygwin@cygwin.com References: <20040827101109.GK27978@cygbert.vinschen.de> <200408280228.i7S2SIs3014737@mx3.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200408280228.i7S2SIs3014737@mx3.redhat.com> User-Agent: Mutt/1.4.2i On Aug 27 21:27, Gary R. Van Sickle wrote: > > On Aug 26 22:48, Gary R. Van Sickle wrote: > > > Well, I just did my 2 minute due diligence and looked up the > > > difference between advisory and mandatory file locking. Did I read > > > right? Does advisory locking actually in no way prevent > > write access to the "locked" > > > file unless all the interested processes also explicitly > > use lockf() etc? > > > > Yes. > > > > Wow. Is this acually a useful thing, or just an unseemly holdover from the > bad-old-days? Yes, this is a useful thing. Also POSIX does only define advisory locking. See "mandatory.txt" in the Linux docs for more information. > Hmmm. Well, is there some reason you couldn't just use LockFile{Ex} et al? > Any apps that are expecting to simultaneously write to the same file without > "real" locking are busted anyway, aren't they? LockFile/LockFileEx are mandatory locking, plus they are far from having POSIX semantics. See MSDN, especially the description of UnlockFileEx. Corinna -- Corinna Vinschen Please, send mails regarding Cygwin to Cygwin Project Co-Leader mailto:cygwin@cygwin.com Red Hat, Inc. -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/