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Path: sserve!manuel!munnari.oz.au!uunet!wupost!usc!sdd.hp.com!caen!hellgate.utah.edu!fcom.cc.utah.edu!cs.weber.edu!terry
From: terry@cs.weber.edu (A Wizard of Earth C)
Subject: Re: Problems with select() and serial ports
Message-ID: <1992Aug19.014931.26539@fcom.cc.utah.edu>
Sender: news@fcom.cc.utah.edu
Organization: Weber State University (Ogden, UT)
References: <1992Aug18.034054.4016@timesink.spk.wa.us>
Date: Wed, 19 Aug 92 01:49:31 GMT
Lines: 41
In article <1992Aug18.034054.4016@timesink.spk.wa.us> kew@timesink.spk.wa.us (Keith Walker) writes:
>
>I recently got 386bsd 0.1 going on my machine and not too long after that
>installed Chris Demetriou's serial driver, which really works good in spite
>of the much maligned copyright :-)
>
>But, the select() call doesn't seem to work right when calling the serial
>ports. The behaviour is easy to replicate; just press ESC when in vi. The
>escape will not be recognized until another character is received. So, it
>seems the timeout isn't working right when there's only one character to be
>read.
>
>Hmmm.
>
>I am not a kernel guru, nor do I play one on the net. I'm hoping someone
>else out there (maybe cgd?) will have some idea of what the problem is or
>maybe even have a fix.
I play one on the net 8-).
A patch to the original driver (not Chris', unfortunately) was posted in this
news group some articles back (when I extract something to make a patch
directory, I remove it, so I can't give you a ref #).
You can play a kernel guru on the net too! The fix is to make the device
numbers start with 0 rather than 1 so that select will get the correct index
to do it's thing. Currently, a select() on an open com1 selects on the 2nd
port (com2) and a select() on an open com2 selects on the third (probably
non-existant) port (com3).
Terry Lambert
terry_lambert@gateway.novell.com
terry@icarus.weber.edu
---
Any opinions in this posting are my own and not those of my present
or previous employers.
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terry@icarus.weber.edu
"I have an 8 user poetic license" - me
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