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Date: Tue, 15 Jul 2003 00:17:54 -0700
From: Terry Lambert <tlambert2@mindspring.com>
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To: Petri Helenius <pete@he.iki.fi>
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cc: Julian Elischer <julian@elischer.org>
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Subject: Re: dumb KSE question
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Petri Helenius wrote:
> >The proper thing to do is perform a blocking operation on the device
> >itself, and unblock it when the condition is true in order to signal
> >the user space process.
> 
> Which of the available operations would you recommend for this purpose
> if no data is transferred between kernel and user when the go ahead
> is signaled?

An ioctl() that sets a flag that it wants a wakeup, and then calls
tsleep().  Signal by calling wakeup() on the sleep address.

-- Terry