+ If you specify a path then the directories will be created up to the
+ main directory for the file. So for example if you specify
+ ``filename_format=a/b/c/$jobnum`` then the directories a/b/c will be
+ created before the file setup part of the job. If you specify
+ :option:`directory` then the path will be relative that directory,
+ otherwise it is treated as the absolute path.
+