test_multiprocessing.py 文件源码

def test_fd_transfer(self):
        if self.TYPE != 'processes':
            self.skipTest("only makes sense with processes")
        conn, child_conn = self.Pipe(duplex=True)

        p = self.Process(target=self._writefd, args=(child_conn, b"foo"))
        p.daemon = True
        p.start()
        with open(test_support.TESTFN, "wb") as f:
            fd = f.fileno()
            if msvcrt:
                fd = msvcrt.get_osfhandle(fd)
            reduction.send_handle(conn, fd, p.pid)
        p.join()
        with open(test_support.TESTFN, "rb") as f:
            self.assertEqual(f.read(), b"foo")