[TCLCORE] Possible Notifier Update?

[Donal K. F. <don...@ma...>]

Hi everyone

At the weekend I was reading this month's Dr Dobbs, and in between all 
the bits about security written by people who don't realize what a 
multi-layered problem it is (and the usual Web-Services junk) there was 
an article on doing high performance asynchronous I/O.  Much of it was 
on IO Completion Ports, comprehension of which I'll leave to David 
Gravereaux, but there was also some discussion of UNIX select(), and how 
/dev/poll was a higher-capacity API onto the same thing.

Now, this set me thinking about whether Tcl's notifier could be adjusted 
to use this new API.  The general semantics is pretty much the same, of 
course, so scripts and even most (all?) C extensions would never see the 
difference.  It would mean a substantial rewrite of some of the 
notifier, but I think that could be done fairly easily.  The main 
problem that I can see is working out whether to use this new API or the 
old select() stuff (which is definitely still needed for older systems.) 
  But I reckon that we could probably get away with just making it a 
feature to be turned on explicitly at configure time (using the 
principle of not making software too smart for its own boots ;^))

I'm also told by Pat Thoyts that kqueue() is another API in this same 
general area.  I know less about it though (not that I know much about 
/dev/poll stuff, just what I read in the article.)

Anyway, my basic question is whether it is a good idea to pursue this 
sort of thing further?  I think we can localize the changes within the 
core well enough that the only way people will notice the difference is 
that their scripts suddenly go a bit faster in their fileevent handling.

Donal.