There seem to have been a bunch of filesystem-related releases
recently.  So I'm not sure if one of them would address my problem
better than something that's in the standard library.

I'm starting a bunch of applications and need to write their stdout
and stderr to logs.  Log files are stored at /<some_base_path>/<user
name>/<application name>.log.

What's the simplest way of creating all those directories (assuming
that none of them exist)?