On Wed, 3 Mar 2004, Quinn wrote:

At 5:55 +0100 3/3/04, Ragnar Sundblad wrote:

...

Apple Q&A 1242 says:

Marek did a fine job of answering your questions but, seeing as I

wrote the Q&A in question, I feel obliged to follow up with more

information.

Thanks! :)

Finally, I'd like to reiterate the comments I made in the Q&A. The

fact that Apple doesn't encourage or support stacking doesn't mean

that you can't do it. It just means that a) you can't get official

support from DTS, and b) you will probably suffer more binary

compatibility problems than if you were developing a supported

product. However, we have no secrets--the entire kernel source is

available via Darwin--and there's a variety of unofficial support

resources (such as this list). Marek is even using this technology

in a commercial product and he hasn't (yet) been abducted by the

Apple Kernel Purity Police (tm) (-:

I can vouch for this! (This made my day Quinn :) ) However, in version 2.0 of our product we are very likely going to switch to the style of WebDav's file system for a number of reasons. One of them being that Apple has to keep WebDav working, so anything we steal^H^H^H^H^Hborrow from there will probably mirror into something in future variations of the VFS layer. Also I have a much better understanding of whats going on at this layer than when I started this project, which also helps... One thing that I am worried about is how much of a speed hit one would take having data going User -> Kernel -> User -> Kernel for a lot or most of the file system calls. MIG RPC's clearly have a good amount of overhead, and WebDav which I believe uses UNIX sockets, still seems like a sluggish file system in general, though maybe http has more to blame on that one than the boundary bounces. Any thoughts on this Quinn? :) --- Marek Kozubal marek@portents.com _______________________________________________ darwin-kernel mailing list | darwin-kernel@lists.apple.com Help/Unsubscribe/Archives: http://www.lists.apple.com/mailman/listinfo/darwin-kernel Do not post admin requests to the list. They will be ignored.