MacOS 10.5 (Leopard) has replaced the kernel debugging tool KTrace with a new tool called DTrace.
KTrace was relatively simple to use, and although not probably the best tool around for looking at what the kernel is doing - it did give you information that you needed simply and easily.
For those of you who might even be marginally interested in DTrace.
Here's a link on MacTech.
And thats just the tip of the iceberg.
Great - something completely new to try and understand. Why couldn't Apple have left KTrace and its friends on the 10.5 system, so we could use it, while we got to grips with DTrace?
Looks like DTruss will do the trick....