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Subject: Re: Can't set CREAD flag on serial port?
References: <873c908a8q DOT fsf AT shadizar DOT dyndns DOT org>
From: mbarilli AT midsouth DOT rr DOT com
Date: Tue, 24 Feb 2004 20:30:12 -0600
In-Reply-To: <873c908a8q.fsf@shadizar.dyndns.org> (mbarilli@midsouth.rr.com's message of "Tue, 24 Feb 2004 14:59:17 -0600")
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>>>>> "me" == mbarilli  <mbarilli AT midsouth DOT rr DOT com> writes:

    me> I'm trying to write an application to access a serial port on
    me> a Windows 2000 box, but the CREAD flag doesn't stay set when I
    me> do `tcsetattr' and check the values with `tcgetattr'.  Trying
    me> to read from the port returns a ``Resource temporarily
    me> unavailable'' error (as generated from perror).

    me> ...

    me>     tty_fd = open("/dev/com2",O_RDWR|O_NDELAY|O_BINARY);

Doh.  Guess that's what I get for cargo-cult programming and not
reading the flags I'm passing to `open'.  Of course I'll get an error
of EAGAIN if I open the port in non-blocking mode (O_NDELAY) and
there's nothing available on the wire.  The CREAD flag issue was a red
herring, apparently.

Sorry 'bout that ...

-- 
Michael J. Barillier               | ``Those who make peaceful
email: mbarilli(at)midsouth.rr.com | revolution impossible will make
web: <http://shadizar.dyndns.org/> | violent revolution inevitable.''
Public key available on request.   |     -- John F. Kennedy

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