nonblocking i/o on windows?

[Skip Montanaro]

At the end of asyncore.py a non-blocking file_dispatcher class is defined
like so:

    class file_dispatcher (dispatcher):
        def __init__ (self, fd):
            dispatcher.__init__ (self)
            self.connected = 1
            # set it to non-blocking mode
            flags = fcntl.fcntl (fd, fcntl.F_GETFL, 0)
            flags = flags | os.O_NONBLOCK
            fcntl.fcntl (fd, fcntl.F_SETFL, flags)
            self.set_file (fd)

        def set_file (self, fd):
            self._fileno = fd
            self.socket = file_wrapper (fd)
            self.add_channel()

Unfortunately, this uses fcntl, which is only available on Unix systems.  Is
there something similar on Windows that will allow me to put a Python file
object in non-blocking mode?  I thought perhaps there would be something
defined in msvcrt, but I didn't see anything in the lib ref manual or the
msvcrt source.

Thx,

-- 
Skip Montanaro (skip at pobox.com - http://www.mojam.com/)
"As often happens in Net communities, people find all kinds of energy to
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