从Python 3.7.6转到Python 3.10.3后找不到DLL

发布于 2025-01-17 17:41:54 字数 1677 浏览 2 评论 0原文

我正在尝试将库升级到 Python 3.10。到目前为止，我一直使用3.7.6。

在我的库中，我使用 DLL。在包 __init__.py 中，我将 DLL 路径添加到 PATH 变量中。因为我想让代码与 32 和 64 位系统兼容，所以我在运行时检查位数并将适当的 DLL 文件夹添加到 PATH：

import os
import sys

# Add libs to PATH environment variable such that DLLs can be loaded.
# Load either x64 or x86 depending on whether we are running a 32/64
# bit system.
package_directory = os.path.dirname(os.path.abspath(__file__))
if sys.maxsize > 2**32:
    path_dir = os.path.join(package_directory, 'libs', 'x64')
else:
    path_dir = os.path.join(package_directory, 'libs', 'x86')

os.environ['PATH'] += os.pathsep + path_dir

相应的文件夹结构是

package_root
|- libs
   |- x64
      |- libbristolpolled.dll
      ...
   |- x86
      |- libbristolpolled.dll
      ...

然后在子包中，我正在使用：

from ctypes import CDLL

dll = "libbristolpolled.dll"
_lib_bristlp = CDLL(dll)

这已经有效在 3.7.6 中很好，但在 3.10.3 中失败，并显示以下错误消息：

  File "C:\...\lib\site-packages\optoMD\sensor\optical\bristol\dll_api.py", line 37, in <module>
    _lib_bristlp = CDLL(dll)  # The correct DLL
  File "C:\Program Files\Python310\lib\ctypes\__init__.py", line 374, in __init__
    self._handle = _dlopen(self._name, mode)
FileNotFoundError: Could not find module 'libbristolpolled.dll' (or one of its dependencies). Try using the full path with constructor syntax.

如果我改为使用绝对路径，如错误消息所示，它可以工作：

from ctypes import CDLL

dll = r"C:\...\libs\x64\libbristolpolled.dll"
_lib_bristlp = CDLL(dll)

旧方法不再工作的原因是什么，或者如何我能让它再次工作吗？我不想在代码中使用绝对路径，而且我喜欢在 init 文件中处理一次 DLL 路径，然后只需要使用文件名导入 DLL 即可。

原文

I am trying to upgrade a library to Python 3.10. Up to now, I have been using 3.7.6.

In my library, I am using DLLs. In the package __init__.py, I add the DLL path to the PATH variable. Since I want to have the code compatible with 32 and 64 bit systems, I check the bitness at runtime and add the appropriate DLL folder to the PATH:

import os
import sys

# Add libs to PATH environment variable such that DLLs can be loaded.
# Load either x64 or x86 depending on whether we are running a 32/64
# bit system.
package_directory = os.path.dirname(os.path.abspath(__file__))
if sys.maxsize > 2**32:
    path_dir = os.path.join(package_directory, 'libs', 'x64')
else:
    path_dir = os.path.join(package_directory, 'libs', 'x86')

os.environ['PATH'] += os.pathsep + path_dir

The corrresponding folder structure is

package_root
|- libs
   |- x64
      |- libbristolpolled.dll
      ...
   |- x86
      |- libbristolpolled.dll
      ...

Then in a sub-package, I am using:

from ctypes import CDLL

dll = "libbristolpolled.dll"
_lib_bristlp = CDLL(dll)

This has worked fine in 3.7.6 but fails in 3.10.3 with the following error message:

  File "C:\...\lib\site-packages\optoMD\sensor\optical\bristol\dll_api.py", line 37, in <module>
    _lib_bristlp = CDLL(dll)  # The correct DLL
  File "C:\Program Files\Python310\lib\ctypes\__init__.py", line 374, in __init__
    self._handle = _dlopen(self._name, mode)
FileNotFoundError: Could not find module 'libbristolpolled.dll' (or one of its dependencies). Try using the full path with constructor syntax.

If I instead use the absolute path, as the error message suggests, it works:

from ctypes import CDLL

dll = r"C:\...\libs\x64\libbristolpolled.dll"
_lib_bristlp = CDLL(dll)

What is the reason the old method doesn't work anymore, or how can I make it work again? I'd prefer not to have absolute paths in my code and I liked the fact that I handle the DLL path once in the init file and afterwards I just need to import the DLL using the file name.

分享到QQ

分享到微博

如果你对这篇内容有疑问，欢迎到本站社区发帖提问参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。

发布评论

需要登录才能够评论，你可以免费注册一个本站的账号。

硬不硬你别怂 2025-01-24 17:41:54

此特定功能（通过将查找 .dll 的路径添加到 PATH 环境变量）已在 Python 3.8 中删除。根据通知，新函数 os.add_dll_directory；引用文档说明更改的原因：

版本 3.8 中的新功能：以前版本的 CPython 将使用当前进程的默认行为解析 DLL。这导致了不一致，例如有时仅搜索 PATH 或当前工作目录，并且 AddDllDirectory 等操作系统功能不起作用。

未来更可移植的解决方案是尝试使用该函数，或者只生成绝对路径，就像您当前使用 os.path.dirname 和 os.path.join 所做的那样> 在 dll 变量上 - 即保持与之前的 Python 版本的兼容性；另外，这还假设这些 .dll 文件没有外部依赖项，如果有的话，此线程有关当前问题的更多详细信息（即使使用绝对路径 - 尽管考虑到它确实适用于您的程序和库，但这对于您的用例来说不应该是问题）。