Python ctypes create_string_buffer() 错误 0xC0000005

Question

我有一个带主循环的命名管道服务器，我在其中从管道读取数据：

while True:
        bytes_available = DWORD()
        ret_code = windll.kernel32.PeekNamedPipe(pipe, None, 0, None, byref(bytes_available))
        if ret_code == 0 and windll.kernel32.GetLastError() == ERROR_BROKEN_PIPE:
            reconnect()
        buf = create_string_buffer(bytes_available.value)
        ret_code = windll.kernel32.ReadFile(pipe, byref(buf), bytes_available.value, None, overlapped_struct_ptr)
        if ret_code != 0 and bytes_available.value > 0:
            # process(buf.raw)
            pass
        elif ret_code == 0 and windll.kernel32.GetLastError() == ERROR_BROKEN_PIPE:
            reconnect()
        windll.kernel32.GetQueuedCompletionStatus(iocp, byref(bytes_transferred), byref(completion_key),
                                                  byref(overlapped_struct_ptr), INFINITE)

有时它会在 create_string_buffer() 步骤崩溃并显示以下消息：

Process finished with exit code -1073741819 (0xC0000005)

这对我来说似乎很奇怪，因为如果我用 (c_char*bytes_available.value)() 替换 create_string_buffer(bytes_available.value) 一切正常。如果我们查看 create_string_buffer() 实现，我们将看到，它以相同的方式分配缓冲区：

def create_string_buffer(init, size=None):
    """create_string_buffer(aString) -> character array
    create_string_buffer(anInteger) -> character array
    create_string_buffer(aString, anInteger) -> character array
    """
    if isinstance(init, (str, unicode)):
        if size is None:
            size = len(init)+1
        buftype = c_char * size
        buf = buftype()
        buf.value = init
        return buf
    elif isinstance(init, (int, long)):
        buftype = c_char * init
        buf = buftype()
        return buf
    raise TypeError(init)

那为什么会失败呢？

Answer 1

windll.kernel32.PeekNamedPipe() 在您的代码中调用似乎缺少一个参数，应该有六个；见 msdn

省略参数本质上会导致未定义的行为。

Python ctypes create_string_buffer() 错误 0xC0000005

Python ctypes create_string_buffer() Error 0xC0000005

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