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Date: Mon, 16 Jun 2003 22:10:58 -0700
From: Terry Lambert <tlambert2@mindspring.com>
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Subject: Re: kqueue alternative?
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Joshua Oreman wrote:
> > >I would say, use select(2).
> > >Is there a reason this wouldn't work?
> >
> > Select doesn't work with files.
> 
> Really? `man 2 select' says nothing about that. It just talks about
> 'file descriptors'. Now if it said 'socket descriptors' or 'non-file
> file descriptors' I would understand, but I don't think that that statement
> is implied by the man page. Is there something I'm missing?

Select blocks on readfds if a read from the file would block;
that is never the case with a file: you will either get data,
or you will get an EOF.  Select blocks on writefds if a write
to the file would block; that is never the case with a file:
you will either successfully write, or you will get an error,
e.g. as a result of exceeding quota, etc..

Therefore a select for reads or writes on a disk file should
always return true.

-- Terry