Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!mcsun!ukc!acorn!dave
From: dave@acorn.co.uk (David Lamkin)
Newsgroups: comp.unix.sysv386
Subject: HELP: DCD failure detection with polled reads (SCOV.3.2)
Summary: Help wanted: DCD failure detection in SCO unix
Keywords: carrier,tty,serial,modem
Message-ID: <4933@acorn.co.uk>
Date: 1 Feb 91 14:21:51 GMT
Distribution: comp
Organization: Acorn Computers Limited, Cambridge, UK
Lines: 12


I'm having trouble detecting carrier fail from my Hayes compatible
modem on my SCO Unix V.3.2 release 2 system. The application is using
serial lines as a background data transfer (so I can't make the
serial line tty my controlling terminal) & I was hoping to avoid the
need for a separate process by setting VMIN & VTIME to 0 and thus poll
on my reads. Everything works fine but when the carrier drops reads
just return "no bytes read".  Am I liable to be able to make this
work? (All the example of code I can find use blocking reads...)

David Lamkin
dlamkin@acorn.co.uk