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From: rock@cbnews.att.com (Y. Rock Lee)
Newsgroups: comp.unix.questions,comp.unix.wizards,comp.unix.internals
Subject: Re: opening tty devices with getty attached
Message-ID: <1991Feb5.143833.19539@cbnews.att.com>
Date: 5 Feb 91 14:38:33 GMT
References: <6853@alpha.cam.nist.gov>
Organization: AT&T Bell Laboratories
Lines: 16

In article <6853@alpha.cam.nist.gov> coleman@cam.nist.gov (Sean Sheridan Coleman X5672) writes:
>
>Now for the confusion. With login ( ie getty engaged) turned on`
>in /etc/ttytab, the open will block with O_NDELAY set. Reading
>through the man pages for the zs devices, I got the idea it was
>suppose to, but I want some confirmation because the man pages
>are not clear about this point. If it is suppose to hang, has
>getty done something to make this happen?

Yes, it is supposed to hang because the standard line discipline
used by the character tty driver doesn't support O_NDELAY.
On the other hand, O_NDELAY is supported by the streamhead in SVR4.


Y. Rock Lee, att!cblph!rock
             rock@cblph.ATT.COM