From owner-freebsd-hackers@FreeBSD.ORG  Fri Apr 29 13:01:10 2005
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From: "Daniel O'Connor" <doconnor@gsoft.com.au>
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Date: Fri, 29 Apr 2005 22:30:32 +0930
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Subject: Re: open("/dev/cuaaX") is slow
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On Fri, 29 Apr 2005 20:56, Andrew L. Neporada wrote:
> It seems that reopening /dev/cuaaX devices after close() takes exactly
> 3 seconds on FreeBSD 4.10 (sorry, I've no 5.x systems available at the
> moment).
>
> Here is output of attached program:
> open() time: 155 us
> open() time: 2995729 us
> open() time: 2999811 us
> open() time: 2999608 us
> open() time: 2999711 us
> open() time: 2999720 us
> open() time: 2999713 us
> open() time: 2999744 us
> open() time: 2999673 us
> open() time: 2999706 us
>
> Is this 3 second delay necessary? Can I get rid of it?

man comcontrol
Try trimming the dtrwait value back and see how it goes.

(Although I'm not sure why you want to open/close a serial port so frequent=
ly)

=2D-=20
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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