def _mapped_std_streams(lookup_paths, streams=('stdin', 'stdout', 'stderr')):
    """Get a mapping of standard streams to given paths."""
    # FIXME add device number too
    standard_inos = {}
    for stream in streams:
        try:
            stream_stat = os.fstat(getattr(sys, stream).fileno())
            key = stream_stat.st_dev, stream_stat.st_ino
            standard_inos[key] = stream
        except Exception:  # FIXME UnsupportedOperation
            pass
        # FIXME if not getattr(sys, stream).istty()

    def stream_inos(paths):
        """Yield tuples with stats and path."""
        for path in paths:
            try:
                stat = os.stat(path)
                key = (stat.st_dev, stat.st_ino)
                if key in standard_inos:
                    yield standard_inos[key], path
            except FileNotFoundError:  # pragma: no cover
                pass

    return dict(stream_inos(lookup_paths)) if standard_inos else {}
Get a mapping of standard streams to given paths.