Wrap System.Posix.Env?

[Anrock]

Most of it can be implemented by plain reexport or simple wrapping of functions from System.Environment of base. Though base lower bound have to be bumped to 4.7 for setEnv.

[joeyh]

I have some code in git-annex that does just that, http://source.git-annex.branchable.com/?p=source.git;a=blob;f=Utility/Env.hs;h=c56f4ec23c09f242eb5b17a77e1df82eea53250a;hb=HEAD -- feel free to reuse that.

Note there's a subtlety on Windows that setting an envvar to "" unsets it. So, setEnv var "" True >> getEnv var yields Nothing on Windows but Just "" on POSIX. I don't know of a way to avoid that difference.