Re: [Haskell-cafe] Re: "C" buffer suggestions??

On Mon, Jun 23, 2008 at 12:07 PM, Adam Langley wrote:

2008/6/23 Galchin, Vasili :

...

Basically I want to model POSIX async io "aiocb"( http://uw714doc.sco.com/en/man/html.5/aiocb.5.html) in Haskell .. in particular the aiocb field "aio_buf"!

That's a mutable buffer, so this has to be pretty low level in your wrapping of the AIO interface. I would keep it as a Ptr Word8 at that point. ByteStrings are probably the correct type for the user visible interface, but I would guess not here.

I tried to write a test value of Word8 without success. Can you give an example?

Plus, ByteString data lives in the Haskell heap so could get moved about by the collector. Since an AIO interface is probably going to return while the IO is still in progress, you don't want to stop the collector, but nor do you want the data moving because the kernel's pointer isn't going to move with it.

^^ Interesting about moving around in the heap. I cannot use it for AIO.

AGL

-- Adam Langley agl@imperialviolet.org http://www.imperialviolet.org