Path: utzoo!utgpu!water!watmath!clyde!cbosgd!ihnp4!chinet!clif
From: clif@chinet.UUCP (Clif Flynt)
Newsgroups: comp.unix.xenix
Subject: termio under SCO Xenix
Message-ID: <2113@chinet.UUCP>
Date: 14 Jan 88 20:18:07 GMT
Reply-To: clif@chinet.UUCP (Clif Flynt)
Organization: Chinet - Public Access Unix
Lines: 39


This is either a bug in my understanding of termio, or a bug in SCO's
implementation.  I'd be happy to hear either confirmed, since I've 
found a workaround.

The situation is that I need to watch keystrokes coming in from console,
and distinguish the difference between a function key ( '<ESC> [ G' for
example) and an escape.  My thought was that I'd set the VMIN and VTIME
parameters in termio, turn off ICANON, and if I timed out, then I'd
recieved a bare escape, not the start of a function key.

So, I tried:

nterm.c_cc[VMIN] = 1;
nterm.c_cc[VTIME] = 2;
nterm.c_lflag &= !ICANON;

ioctl...

My understanding is that a read will return when it recieved VMIN char's
(one character) or it times out after .2 seconds.

The reads never timed out, though I did get each character typed as
soon as the key was pressed.

When I changed VMIN to 0, I got the behavior I expected to see, with
timeouts happenning after .2 seconds.  The read returns 0 for a count
of characters read if timeout, and 1 if it reads a char.

So, my question is, why didn't I time out when VMIN was > 0?  Should I
time out, (is this a bug) or should VMIN take precedence over VTIME (an
error in my comprehension).

Thanks for any info folks supply.
-- 
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My Opinions are my own. I can't imagine why anyone else would want them.
Clif Flynt	ihnp4!chinet!clif
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