Changed behaviour when reading from FIFOs!

[Volker Stolz]

On Mon, Oct 29, 2001 at 02:08:23PM -0000, Simon Marlow wrote:
> This appears to be because the dummy Handle opened in WriteMode is being
> garbage collected and closed, which leaves the FIFO with no writers so
> you get EOF.  5.02 is behaving correctly here.  You can add an extra
> 'hClose dummy' at the end of 'main' to prevent the EOF exception.

Argh, that was exactly what I feared when I read the file-handles
discussion on the list. Only I didn't realize that the feature
got indeed introduced into ghc-5.02.

> You have some extra blocking in there: just comment out the first two
> lines  of fifoReadLoop, and everything should be fine.  This also fixes
> the other problem you mentioned above ("varying numbers of last").

The blocking is essential since I need to be able to use MVars
between the threadWaitRead & the hGetLine (remember the note I
sent about fork()ing).
-- 
Volker Stolz * vs at foldr.org * PGP + S/MIME