forcing a haskell object to WHNF from C

[Bernard James POPE]

Hi all,

This might seem like a strange thing to do, but ...

Presume I have a HaskellObj in some C code. I know that it is a thunk.
I want to force it to _WHNF_ .

Should/can I use rts_eval()? 

Any pointers on what this does (start new threads, cause garbage collection
...) would be appreciated. I can (and have) gone over the code but a more
high level description would be helpful.

Or perhaps there is another/better way.

In essence I want a C version of seq (perhaps I can call to Haskell to
perform a seq on it, but I think this might be overkill). 

A lightweight solution would be nice.

Cheers,
Bernie.