Class PipeHandle

Lib/asyncio/windows_utils.py:88–126

Wrapper for an overlapped pipe handle which is vaguely file-object like. The IOCP event loop can use these instead of socket objects.

class PipeHandle:
    """Wrapper for an overlapped pipe handle which is vaguely file-object like.

    The IOCP event loop can use these instead of socket objects.
    """
    def __init__(self, handle):
        self._handle = handle

    def __repr__(self):
        if self._handle is not None:
            handle = f'handle={self._handle!r}'
        else:
            handle = 'closed'
        return f'<{self.__class__.__name__} {handle}>'

    @property
    def handle(self):
        return self._handle

    def fileno(self):
        if self._handle is None:
            raise ValueError("I/O operation on closed pipe")
        return self._handle

    def close(self, *, CloseHandle=_winapi.CloseHandle):
        if self._handle is not None:
            CloseHandle(self._handle)
            self._handle = None

    def __del__(self, _warn=warnings.warn):
        if self._handle is not None:
            _warn(f"unclosed {self!r}", ResourceWarning, source=self)
            self.close()

    def __enter__(self):
        return self

    def __exit__(self, t, v, tb):
        self.close()


# Replacement for subprocess.Popen using overlapped pipe handles