I've beeing writing a low-level binding to posix that can be usefull if you want to use posix but has no time to learn FFI: http://hackage.haskell.org/package/bindings-posix However, my understandment of posix is barely nothing, and I see that many of its functionality is enabled or disabled by macros, and I don't know which ones are related to what functionality. So, if you know about that: would you be able to list all macros (or at least most important ones, if there are too many) that enable all (or most) of posix? In exchange, you get a posix binding that is actually comprehensive :) Thanks, Maurício