Concurrent import of astropy occasionally fails with likely race condition on config files. #7290
Description
When trying to import astropy from an MPI application ( with 128 ranks), the application crashes during first import randomly with a file system error.
It appears that some astropy instances are trying to modify a configuration file while some others are trying to read it.
from astropy.cosmology import Planck13, Planck15, WMAP5, WMAP7, WMAP9
File "/dev/shm/local/lib/python3.6/site-packages/astropy/__init__.py", line 286, in <module>
log = _init_log()
File "/dev/shm/local/lib/python3.6/site-packages/astropy/logger.py", line 97, in _init_log
log._set_defaults()
File "/dev/shm/local/lib/python3.6/site-packages/astropy/logger.py", line 473, in _set_defaults
self.setLevel(conf.log_level)
File "/dev/shm/local/lib/python3.6/site-packages/astropy/config/configuration.py", line 273, in __get__
return self()
File "/dev/shm/local/lib/python3.6/site-packages/astropy/config/configuration.py", line 396, in __call__
sec = get_config(self.module)
File "/dev/shm/local/lib/python3.6/site-packages/astropy/config/configuration.py", line 530, in get_config
cobj = configobj.ConfigObj(cfgfn, interpolation=False)
File "/dev/shm/local/lib/python3.6/site-packages/astropy/extern/configobj/configobj.py", line 1228, in __init__
self._load(infile, configspec)
File "/dev/shm/local/lib/python3.6/site-packages/astropy/extern/configobj/configobj.py", line 1317, in _load
raise error
astropy.extern.configobj.configobj.ParseError: Invalid line ('\x00\x00\x00\x00\x00\x00\x00\x00\x00
....