Re: LPT interruptstorm

From: Daniel O'Connor <doconnor_at_gsoft.com.au>
Date: Tue, 3 Aug 2004 13:58:55 +0930
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On Mon, 2 Aug 2004 21:19, Ian FREISLICH wrote:
> suggested 'lptcontrol -e', but every time I've tried that (even
> with lpd stopped) I get 'lptcontrol: open: Device busy'.  I'm not
> sure what keeps the printer port open other than lpd.

For some reason you can't open /dev/lpt* when something isn't driving the BUSY 
line on the parallel port :(

Actually I just read the code some more :)
You could try

lptcontrol -d /dev/lpt0.ctl -X

lpt0.ctl has the bypass flag (0x80) set in the minor number which prevents 
lptopen() from trying to talk to the hardware (see
/usr/src/sys/dev/ppbus/lpt.c:478)

I think lptcontrol could do with this diff (attached)

- -- 
Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
are so many of them to choose from."
  -- Andrew Tanenbaum
GPG Fingerprint - 5596 B766 97C0 0E94 4347 295E E593 DC20 7B3F CE8C
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Received on Tue Aug 03 2004 - 02:29:06 UTC

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