adb: fix test_sighup.

            trap "echo SIGINT > {path}; exit 0" SIGINT

            trap "echo SIGHUP > {path}; exit 0" SIGHUP

            echo Waiting

            while true; do sleep 100; done

            read

        """.format(path=log_path)

        script = ";".join([x.strip() for x in script.strip().splitlines()])

        process = self.device.shell_popen(

            ["sh", "-c", "'{}'".format(script)], kill_atexit=False, stdout=subprocess.PIPE)

        process = self.device.shell_popen([script], kill_atexit=False,

                                          stdin=subprocess.PIPE,

                                          stdout=subprocess.PIPE)

        self.assertEqual("Waiting\n", process.stdout.readline())

        process.send_signal(signal.SIGINT)

        # Waiting for the local adb to finish is insufficient, since it hangs

        # up immediately.

        time.sleep(0.25)

        time.sleep(1)

        stdout, _ = self.device.shell(["cat", log_path])

        self.assertEqual(stdout.strip(), "SIGHUP")