toy module to temporarily redirect a program's stdout

 Due to the design of POSIX, it is possible to temporarily overload the
 file descriptors corresponding to stdout and stderr to point to an
 arbitrary pipe. It is, however, tricky to get right. This module gets
 it right, as far as such a terrible hack can be made right. It can be
 used to make misbehaving third-party C libraries stop spewing to
 standard output.
 .
 This package provides a library for the Haskell programming language.
 See http://www.haskell.org/ for more information on Haskell.