From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Tobias Schandinat Subject: Re: open and close semanthics Date: Fri, 28 Aug 2009 11:43:28 +0200 Message-ID: <4A97A6C0.1000006@gmx.de> References: <4A946A59.20307@manoweb.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from sfi-mx-1.v28.ch3.sourceforge.com ([172.29.28.121] helo=mx.sourceforge.net) by 335xhf1.ch3.sourceforge.com with esmtp (Exim 4.69) (envelope-from ) id 1Mgxzd-0007PW-SA for linux-fbdev-devel@lists.sourceforge.net; Fri, 28 Aug 2009 09:43:37 +0000 Received: from mail.gmx.net ([213.165.64.20]) by 29vjzd1.ch3.sourceforge.com with smtp (Exim 4.69) id 1MgxzY-0007fR-Oo for linux-fbdev-devel@lists.sourceforge.net; Fri, 28 Aug 2009 09:43:37 +0000 In-Reply-To: <4A946A59.20307@manoweb.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-fbdev-devel-bounces@lists.sourceforge.net To: Alessio Sangalli Cc: "linux-fbdev-devel@lists.sourceforge.net" Hi, this is not authoritative but I hope that's better than no answer: Alessio Sangalli schrieb: > Hi, can somebody give me an authoritative answer: > what is the semanthics associated to the "open" and "release" (close) calls? > > More specifically, "open" and "release" can/must/must not change any > setting (resolution etc)? > > Should those functions keep a "counter" of how many programs opened it? I'd say that's not well defined. skeletonfb lists them even as optional. I've read that some drivers use it for mode changes, some keep counters and others just return 0. If you are writing a driver: use it as you need it or don't use it at all. If you write something that needs this behavior: there is none you can expect along all drivers, sorry. For more information: http://www.linux-fbdev.org/HOWTO/4.html /drivers/video/skeletonfb.c Regards, Florian Tobias Schandinat ------------------------------------------------------------------------------ Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day trial. Simplify your report design, integration and deployment - and focus on what you do best, core application coding. Discover what's new with Crystal Reports now. http://p.sf.net/sfu/bobj-july