bindings-posix is a low level binding to Posix. http://hackage.haskell.org/package/bindings-posix It is part of bindings-* packages, and makes use of facilities and design from package bindings-common to map the standard Posix library as described in this page: http://www.opengroup.org/onlinepubs/9699919799/basedefs/contents.html The major drawback is that it bindings to the Posix instance that runs on my computer (and probably most computers using ghc and gcc). However, if there's interest, I can add support to various layers of Posix if someone with knowledge of Posix helps me with environment variables I should use to (de)activate specific functionality. Best, Maurício