Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com Delivered-To: mailing list cygwin AT cygwin DOT com Date: Wed, 2 Feb 2005 19:09:29 +0100 From: Corinna Vinschen To: cygwin AT cygwin DOT com Subject: Re: Help about serial programming: manipulating DTR Message-ID: <20050202180929.GQ31117@cygbert.vinschen.de> Reply-To: cygwin AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com References: <6 DOT 0 DOT 1 DOT 1 DOT 0 DOT 20050202171834 DOT 01fcf4f8 AT 192 DOT 168 DOT 2 DOT 1> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <6.0.1.1.0.20050202171834.01fcf4f8@192.168.2.1> User-Agent: Mutt/1.4.2i On Feb 2 17:34, llandre wrote: > Hi all, > > I'm trying to manipulate the DTR signal of the serial port. > As an example I used this code snippet: > http://lists.exploits.org/upsdev/Feb2004/00013.html. > I can open the com1, I can send and receive data but the ioctl I use > to read the status of the signals returns -1: > > int status; > ioctl(upsfd, TIOCMGET, &status); > > Anybody can help me? I have no idea about what's wrong with this code. strace would give a hint. TIOCMGET should only fail because a call to GetCommModemStatus fails. If so, the strace would contain a line which talks about setting errno in fhandler_serial::ioctl. Corinna -- Corinna Vinschen Please, send mails regarding Cygwin to Cygwin Project Co-Leader mailto:cygwin AT cygwin DOT 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/