'L{fdesc.setBlocking} sets a file description to blocking.'

def test_setBlocking(self):

    (r, w) = os.pipe()
    self.addCleanup(os.close, r)
    self.addCleanup(os.close, w)
    fdesc.setNonBlocking(r)
    fdesc.setBlocking(r)
    self.assertFalse((fcntl.fcntl(r, fcntl.F_GETFL) & os.O_NONBLOCK))
