__init__.py 文件源码

def send_signal(self, sig):
        """Send a signal to process pre-emptively checking whether
        PID has been reused (see signal module constants) .
        On Windows only SIGTERM is valid and is treated as an alias
        for kill().
        """
        if POSIX:
            self._send_signal(sig)
        else:  # pragma: no cover
            if sig == signal.SIGTERM:
                self._proc.kill()
            # py >= 2.7
            elif sig in (getattr(signal, "CTRL_C_EVENT", object()),
                         getattr(signal, "CTRL_BREAK_EVENT", object())):
                self._proc.send_signal(sig)
            else:
                raise ValueError(
                    "only SIGTERM, CTRL_C_EVENT and CTRL_BREAK_EVENT signals "
                    "are supported on Windows")