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Date: Tue, 14 Jan 97 23:09:26 +0000
X400-Content-Identifier: Re: select() on 
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To: brandon@cold.org
Cc: freebsd-hackers@FreeBSD.ORG
In-Reply-To: <Pine.NEB.3.95.970114104018.3232A-100000@cold.org>
Subject: Re: select() on a serial device--ignoring OS buffered chars?
Sender: owner-hackers@FreeBSD.ORG
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>         scount = select(1, &read_fds, NULL, NULL, &tv);
                         ^^^
                         This looks like the problem to me.

The select() manpage is a little confusing - that first parameter is the
number of bits in the mask that get inspected, not the number of
active fds ('1' bits).  See selscan() in /sys/kern/sys_generic.c

So unless your FD happens to be zero, this call isn't going to do
anything useful.