Sockets again

[George Russell]

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The attached short program (compile with "ghc VServer.hs -o v -package net")
is supposed to set up a server on port 15151, wait for a connection, read
the first character from the connection, and print it out.  Unfortunately
if I test it, by running it, and starting up "telnet [machine] 15151"
somewhere else, and then type some random text, EG "foo[RETURN]", it does
not work.  It looks as if the problem is that VServer.hs issues the
command
    hSetBuffering handle (BlockBuffering (Just 4096))
on the connection, because when I change it to
    hSetBuffering handle NoBuffering
the program works.

However this is not what I want to do!!  Because setting NoBuffering on the
handle is going to mean that when the Server *outputs* something, it will
potentially be done very expensively character by character.  How do I
get block buffering on the Server's output, but not have input to the
server held up?

The same thing seems to happen with client Handles by the way.

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