/root/.python-eggs 报

部署过程中，使用虚环境，但是启动程序的时候报错，如下：

Traceback (most recent call last):   File "/home/himalayas/fdsearch/fdsearch/bin/fdsearch", line 34, in <module>     from fdsearch import wsgi   File "/home/himalayas/fdsearch/fdsearch/wsgi.py", line 32, in <module>     import fdsearch.domain   File "/home/himalayas/fdsearch/fdsearch/domain/__init__.py", line 20, in <module>     from notify_handler import NotifyHandler   File "/home/himalayas/fdsearch/fdsearch/domain/notify_handler.py", line 23, in <module>     from cjson import encode as json_encode   File "build/bdist.linux-x86_64/egg/cjson.py", line 7, in <module>   File "build/bdist.linux-x86_64/egg/cjson.py", line 4, in __bootstrap__   File "/home/himalayas/virtualenv/python2.7-fd/lib/python2.7/site-packages/pkg_resources.py", line 945, in resource_filename     self, resource_name   File "/home/himalayas/virtualenv/python2.7-fd/lib/python2.7/site-packages/pkg_resources.py", line 1633, in get_resource_filename     self._extract_resource(manager, self._eager_to_zip(name))   File "/home/himalayas/virtualenv/python2.7-fd/lib/python2.7/site-packages/pkg_resources.py", line 1661, in _extract_resource     self.egg_name, self._parts(zip_path)   File "/home/himalayas/virtualenv/python2.7-fd/lib/python2.7/site-packages/pkg_resources.py", line 1025, in get_cache_path     self.extraction_error()   File "/home/himalayas/virtualenv/python2.7-fd/lib/python2.7/site-packages/pkg_resources.py", line 991, in extraction_error     raise err pkg_resources.ExtractionError: Can't extract file(s) to egg cache The following error occurred while trying to extract file(s) to the Python egg cache:   [Errno 13] Permission denied: '/root/.python-eggs' The Python egg cache directory is currently set to:   /root/.python-eggs

解决办法：让开发在代码中声明一下环境变量。

export PYTHON_EGG_CACHE=/some/other/dir

注意：在系统的/etc/profile中声明是没有办法的，因为程序是在虚环境中运行。