Return-Path: From: Marcel Holtmann To: BlueZ users In-Reply-To: <1175283949.5851.3.camel@localhost> References: <1175283949.5851.3.camel@localhost> Date: Sat, 31 Mar 2007 15:44:29 +0200 Message-Id: <1175348669.5815.251.camel@violet> Mime-Version: 1.0 Subject: Re: [Bluez-users] Multithread Service Discovery Reply-To: BlueZ users List-Id: BlueZ users List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Sender: bluez-users-bounces@lists.sourceforge.net Errors-To: bluez-users-bounces@lists.sourceforge.net Hi Malte, > > I'm currently running a C program for service discovery on a list of > > devices. The function loops through the list elements and performs an > > SDP enquiry on each device and returns the results to the screen, but > > I'm finding that if i get a slow device in the list it can hold things > > up a little, and in general it would be fantastic to hit all the > > devices with an enquiry simultaneously. > > Multithreading is possible, I use the OpenThreads library to do so for > the same reasons. Attention, OpenThreads is OO and C++ so you might look > for another solution like pthreads. if you have a recent kernel then this might work since the kernel queues the page requests. However in general a simultaneous service discovery (or name resolving for that matter) is not possible. The chips baseband can only page one remote device at a time. So even if it looks like simultaneous service discovery. It is not. The kernel serializes it for you and this means the same page timeout problems appear when devices are out of range. The only way to speed this up is to change the page timeout value of the Bluetooth chip. Regards Marcel ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Bluez-users mailing list Bluez-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bluez-users