#: 12137 S12/OS9/68000 (OSK)
    08-Sep-91  21:34:01
Sb: #12117-#Intercepts
Fm: Bob van der Poel 76510,2203
To: Kevin Darling 76703,4227 (X)

Well, ummm, errr, okay... Actually, in The OS9 Catalogue, page 21, it does
state that "system state functions and OS-9 interrupt service routines operate
only in sypervisor state..." So I assumed that when, on page 81 of the C
manual, they say "any i/o using the OS-9 C library (eg. printf) _cannot_ be
performed inside both the intercept handler function and the main program" I
figured that was the reason. Bob Taylor's comment about signals being enqueued
makes as much sense. But, then how does one un-enqueue the signals -- this
implies to me that if you were to use an intercept to restart a program (maybe
back to the main menu for a game, or whatever) then you'd only be able to do it
once. Under Level II I have used signals for that purpose, without any
problems. I assumed that (for whatever reason) you could not do it with OSK.
Maybe some more expanations from MW are in order. Also, all the examples from
MW that I've seen do avoid I/O in the intercept (they just set a flag and
return). Guess it's time to stop reading the manual and just write the code.
Also, would it make any difference if one is using the CIO trap for I/O?

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