Hello, On my personal computer, I added some functionality to the unix package and now I want to test this functionality. Basically I did a cabal install to the global env on my laptop. I just ran a session of ghci: vigalchin@ubuntu:~$ ghci GHCi, version 6.8.2: http://www.haskell.org/ghc/ :? for help Loading package base ... linking ... done. Prelude> :m System.Posix Prelude System.Posix> :t openFd openFd :: FilePath -> OpenMode -> Maybe FileMode -> OpenFileFlags -> IO Fd Prelude System.Posix> :t mqOpen <interactive>:1:0: Not in scope: `mqOpen' There is a signature for openFd (existing functionality) but not mqOpen (new functionality!) The new functionality got some warnings vis-a-vis Storage because I have defined "alignment" and something else yet. However, when I did "runhaskell Setup.hs install" everything seemed to get installed. ??? Thanks, B.