I thought I'd look at putting my coding where my mouth is and seeing what would
be involved in getting Event working on Win32.
Basically, it looks like the necessary changes could be pretty straightforward -
the system-specific stuff is localised in c/unix_io.c (and a bit in c/signal.c -
what's rsignal()?) I could probably hash up an IO watcher based on
MsgWaitForMultipleObjects() -- assuming that I can get from a Perl file object
to a Win32 HANDLE (I'm pretty sure I can). But there are two problems there -
first, Win32 waits on file HANDLEs are "discouraged" (I quote the
documentation...) - you;re supposed to use asynchronous IO instead. This is a
minor issue (until MS make it stop working :-() - the major one is that it
misses the point - for Win32, we don't *want* an io watcher, we want a handle
watcher, which watches on *any* type of Win32 waitable object (plus, probably on
the Windows message queue). An io watcher could be a special type of handle
watcher, which automatically translates perl files into WIn32 handles, and then
watches the underlying handle.
But this boils down to the bit in Event::MakeMaker.pm - "BUT I NEED A NEW TYPE
OF WATCHER FOR MY INTERGALACTIC INFEROMETER".
So, how do I go about this? I could work out how to do it from the existing
code, but I'm too idle for that... :-) And the first looks seem to indicate that
I need stuff in the main Event.xs code if I'm to handle it that way, which isn't
something I want to put in lightly. Also, there's the question of whether adding
a new type of event (which has no counterpart on Unix) has portability
implications. But I don't want to force Win32 events to fit the Unix model, any
more than I see the Unix model being mangled to fit the WIn32 model.
Thoughts...?
Paul.
