re-opening a closed stdin?

[Simon Marlow]

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> > You can call 'System.Posix.IO.dup stdin' and save this value.
> > However, I think you then need to explicitely read from this fd as
> > it is not possible to reset what GHC thinks stdin is currently to
> > this new fd (I'll dig into this and maybe we'll get a
> >    setStdin :: Fd -> IO ()
> > from this, IIRC somebody else was asking for this, too).
>=20
> How does this interact with Simon's proposal for hDuplicate?

If you actually want to change what stdin/stdout/stderr refer to, or
re-open one of these file descriptors after it has been closed, then you
need hDuplicateTo.

I've enclosed a version of these functions which works with GHC 5.04.1.

Cheers,
	Simon

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