更新后运行 Jupyter Lab/Notebook 和大多数 Conda 命令时出错

Question

尝试更新 conda 软件包后，我无法再启动 Jupyter Notebook 或 Jupyter Lab。大多数 conda 命令也会导致终端出现错误。虽然每个命令都会导致略有不同的错误，但每个命令都以以下语句终止：

ImportError: dlopen(/Users/USERNAME/anaconda3/lib/python3.7/lib-dynload/_ctypes.cpython-37m-darwin.so, 2): Library not loaded: @rpath/libffi.6.dylib
  Referenced from: /Users/USERNAME/anaconda3/lib/python3.7/lib-dynload/_ctypes.cpython-37m-darwin.so
  Reason: image not found

例如，尝试运行 jupyter lab 会导致：

Traceback (most recent call last):
  File "/Users/USERNAME/anaconda3/lib/python3.7/site-packages/jupyterlab_server/server.py", line 14, in <module>
    from notebook.base.handlers import (
  File "/Users/USERNAME/anaconda3/lib/python3.7/site-packages/notebook/base/handlers.py", line 35, in <module>
    from notebook.utils import is_hidden, url_path_join, url_is_absolute, url_escape
  File "/Users/USERNAME/anaconda3/lib/python3.7/site-packages/notebook/utils.py", line 10, in <module>
    import ctypes
  File "/Users/USERNAME/anaconda3/lib/python3.7/ctypes/__init__.py", line 7, in <module>
    from _ctypes import Union, Structure, Array
ImportError: dlopen(/Users/USERNAME/anaconda3/lib/python3.7/lib-dynload/_ctypes.cpython-37m-darwin.so, 2): Library not loaded: @rpath/libffi.6.dylib
  Referenced from: /Users/USERNAME/anaconda3/lib/python3.7/lib-dynload/_ctypes.cpython-37m-darwin.so
  Reason: image not found

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/USERNAME/anaconda3/bin/jupyter-lab", line 5, in <module>
    from jupyterlab.labapp import main
  File "/Users/USERNAME/anaconda3/lib/python3.7/site-packages/jupyterlab/labapp.py", line 14, in <module>
    from jupyterlab_server import slugify, WORKSPACE_EXTENSION
  File "/Users/USERNAME/anaconda3/lib/python3.7/site-packages/jupyterlab_server/__init__.py", line 4, in <module>
    from .app import LabServerApp
  File "/Users/USERNAME/anaconda3/lib/python3.7/site-packages/jupyterlab_server/app.py", line 9, in <module>
    from .server import ServerApp
  File "/Users/USERNAME/anaconda3/lib/python3.7/site-packages/jupyterlab_server/server.py", line 26, in <module>
    from jupyter_server.base.handlers import (                          # noqa
  File "/Users/USERNAME/anaconda3/lib/python3.7/site-packages/jupyter_server/base/handlers.py", line 34, in <module>
    from jupyter_server.utils import is_hidden, url_path_join, url_is_absolute, url_escape
  File "/Users/USERNAME/anaconda3/lib/python3.7/site-packages/jupyter_server/utils.py", line 10, in <module>
    import ctypes
  File "/Users/USERNAME/anaconda3/lib/python3.7/ctypes/__init__.py", line 7, in <module>
    from _ctypes import Union, Structure, Array
ImportError: dlopen(/Users/USERNAME/anaconda3/lib/python3.7/lib-dynload/_ctypes.cpython-37m-darwin.so, 2): Library not loaded: @rpath/libffi.6.dylib
  Referenced from: /Users/USERNAME/anaconda3/lib/python3.7/lib-dynload/_ctypes.cpython-37m-darwin.so
  Reason: image not found

尝试使用自制程序重新安装 libffi（如其他地方所建议的）也失败了。

任何有关恢复和运行的帮助将不胜感激。

Answer 1

我也遇到了类似的问题，需要将 libffi 降级到版本 3.2.1。

我从未明确安装过 libffi；它是随着原始环境的创建而出现的。

尝试这个

% conda install libffi=3.2.1

我能够安装许多软件包，但 nb_conda_kernels 和各种 jupyter lab 扩展安装失败。