Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!zaphod.mps.ohio-state.edu!van-bc!ubc-cs!uw-beaver!sumax!thebes!campbell
From: campbell@Thalatta.COM (Bill Campbell)
Newsgroups: comp.lang.c
Subject: Re: Acessing modem from C
Message-ID: <4006@thebes.Thalatta.COM>
Date: 4 May 90 15:39:13 GMT
References: <44008@iuvax.cs.indiana.edu>
Reply-To: campbell@Thalatta.COM (Bill Campbell)
Distribution: na
Organization: Thalatta Corporation, Bellevue WA
Lines: 20

In article <44008@iuvax.cs.indiana.edu> mitchemt@silver.ucs.indiana.edu (Terry Mitchem) writes:
:>
:>	HELP!! I am trying to access my modem (under xenix 286). I have no
:>idea how to do this and the manuals arn't very helpful. The modem is on tty1a
:>(1A if you care about modem control). I just need some hints to help me get
:>started. I tried to open tty1a as a file but had no luck. It seems that the
:>modem won't accept anything I write there as a command. Any and all help is 
:>appreciated. Please E-mail if possible.

You need to open with the O_NDELAY to open with no carrier detect.  This
allows the open to succeed before carrier is present.  Without the O_NDELAY
the open waits for carrier.

The best thing for you to do is look at the dialer sources in /usr/lib/uucp
on your Xenix system.
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