The OS could then intercept any attempted access to the directory Envarc:Someappication (assuming it doesnt exist) and look for Env:Someapplication.vars automatically. Conceptually, its not a lot different from a .prefs file, other than the fact its human readable text.
That's one of the really underrated parts of OSX to me. Most pref files, for the OS itself and other apps are .plist files - basically an xml document that holds info as (mostly) readable text.
Part of the benefit is not only that it's human readable, but there's a few commandline utilities for writing to and reading from those .plist files. Apps that wish to use them just use the system tools for creating/managing them. Ideally too, one web browser can read anothers bookmarks, or font prefs or other settings.
For example iTerm, a shell app, has:
-------------------
http://www.apple.com/DTDs/PropertyList-1.0.dtd">
AntiAlias
BlinkingCursor
CopySelection
EnforceCharacterAlignment
HideTab
...etc
Quite an underrated feature... and at a guess 85% of programs/utils/whatever do use .plist files for their preferences.
