RedirectHFile
Class
RedirectHFile
objects should be created whenever you want
to spawn a sub-process and you want that sub-process to inherit
certain specific handles. The constructor redirects a specified IO
handle (OS/2 HFILE) to a specific handle number and insures that
handle is set to be inherited. The destructor un-does everything
and puts all handles back the way they were. These objects should
not be allowed to exist for long, because they lock out other threads.
This class is used to implement the upipestream classes.