Mailing-List:	contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Subscribe:	<mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive:	<http://sources.redhat.com/ml/cygwin/>
List-Post:	<mailto:cygwin AT cygwin DOT com>
List-Help:	<mailto:cygwin-help AT cygwin DOT com>, <http://sources.redhat.com/ml/#faqs>
Sender:	cygwin-owner AT cygwin DOT com
Mail-Followup-To:	cygwin AT cygwin DOT com
Delivered-To:	mailing list cygwin AT cygwin DOT com
Message-Id:	<200309251634.h8PGY1Rr021979@mailhost.nso.edu>
Date:	Thu, 25 Sep 2003 10:34:01 -0600 (MDT)
From:	Craig Gullixson <craig AT nso DOT edu>
Reply-To:	Craig Gullixson <craig AT nso DOT edu>
Subject:	Re: open () and /dev/ttyS0
To:	cygwin AT cygwin DOT com
MIME-Version:	1.0

It turns out that the permission denied error was due to a typeo causing
an attempt to open the serial port a second time (me: bashing head against
wall).  After that was corrected, tty port works fine with my POSIX tty
library.

---Craig

>
>I have an application where I need to communicate with some simple
>controllers via serial commands.  I have a package to do the low level
>open,read,write, and close tasks for a tty port that I have been using
>for a number of years under Solaris using the standard POSIX tty calls.
>
>My problem is that when attempting to open /dev/ttyS0, I get a
>permission denied error.  I get the same error when attempting to
>open /dev/com1.  Curiously, the open works when opening "com1" but
>the tcgetattr () call then fails with a not a typewriter error
>(presumably ENOTTY).
>
>I can manually communicate with the controllers via hyperterm.
>
>My configuration is 
>
>uname -a output:
>
>CYGWIN_NT-5.0 dlsppc 1.5.5(0.94/3/2) 2003-09-20 16:31 i686 unknown unknown 
>Cygwin
>
>The windows system is:
>
>Windows 2000 Professional Ver 5.0 Build 2195 Service Pack 4
>
>built on a FAT32 partition.
>
>
>I have noted several similar problems with opening serial ports in the
>archives but have not see anything regarding this being resolved.
>
>Any suggestions would be appreciated.
>
>---Craig
>
>
>________________________________________________________________________
>Craig A. Gullixson
>Instrument Engineer			INTERNET: cgullixson AT nso DOT edu
>National Solar Observatory/Sac. Peak    PHONE: (505) 434-7065
>Sunspot, NM 88349 USA                   FAX: (505) 434-7029
>


--
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/

- Raw text -