Initializes the given IFFHandle to be a DOS stream. It installs a
"custom" stream handler (via InitIFF) to handle DOS streams.
The iff_Stream field of the iffhandle will still need
to be initializes with a filehandle struct as returned from
dos.library/Open(). The iff_Flags may be changed to
change the seekability of the stream after this function is called,
but before OpenIFF() is called. Seekability for dos files
default to IFFF_RSEEK (random seekable).
INPUTS
iff
pointer to an IFFHandle struct.
RESULT
NOTES
EXAMPLE
BUGS
SEE ALSO
INTERNALS
HISTORY
03.02.1997 digulla
Some major hacks because we don't have A6 - The IFFParseBase must be
passed to the hooks in hook->h_Data.