Xref: utzoo comp.dcom.modems:2714 comp.sys.att:4514
Path: utzoo!utgpu!water!watmath!onfcanim!dave
From: dave@onfcanim.UUCP (Dave Martindale)
Newsgroups: comp.dcom.modems,comp.sys.att
Subject: Re: MORE 6386 UUCP WOES ...
Keywords: cu, Hayes Modem
Message-ID: <16509@onfcanim.UUCP>
Date: 19 Oct 88 17:07:02 GMT
References: <319@argon.UUCP> <2096@cuuxb.ATT.COM> <727@wsccs.UUCP>
Reply-To: dave@onfcanim.UUCP (Dave Martindale)
Organization: National Film Board / Office national du film, Montreal
Lines: 18

In article <727@wsccs.UUCP> terry@wsccs.UUCP (Every system needs one) writes:
>
>The general UNIX implementation of modem-control devices is that of setting
>either bit 6 or 7 of the minor device number.  To find out for sure
>which should be used on your system, check sio(7) in your manual.  In
>general, if the minor device is greater than 64, it's a modem control
>device.

I don't know about system V UNIXes, but on all of the older UNIX versions
plus the BSD variants, the default device supported modem control - it's
the only sane way to handle dialins.

Sometimes an upper bit in the minor devices was used to add a "nowait"
device, that allowed you to talk to the modem without waiting for
Carrier Detect, but this is not always present.

Maybe it is just Xenix that gives you no modem control by default?
This is pretty brain-damaged behaviour.