#: 12158 S12/OS9/68000 (OSK)
    10-Sep-91  03:45:12
Sb: #12137-Intercepts
Fm: Kevin Darling 76703,4227
To: Bob van der Poel 76510,2203 (X)

Bob,

The "interrupt routines" mentioned there, are for cpu interrupts... not user
interrupt service routines (which should just be called: signal service
routines :-)

I just took a quickie non-pro glance with the debugger at the kernel, and what
I see is this:

Whenever your turn to run comes (assumption: from a signal or sleep wakeup or
whatever), the kernel checks to see if you're already in an signal intercept
routine... if so, it cuts right back to you.

Therefore, I would think that normal wakeup driver signaling will still work,
and so doing I/O should be okay (which the exception of getting, say, a BREAK
key or something else that signals you especially).  Ie: don't expect to get
user signals while in the signal intercept routine :-)

If you jump out of your routine back into a main loop (under OSK or OS9), then
you leave a stackframe hanging around, which will slowly eat up your data area
until you crash.  Under OSK of course, you also leave the special "I'm in an
intercept routine" flag hanging, and won't ever enter the signal intercept code
again.  So the F$RTE under OSK is the correct way to exit.

Anyway, just some info.  I'm having to learn about OSK myself :-) kev