[Coco] signal/intercept routine in Basic09

[Wayne Campbell]

Aaron Wolfe came up with a signal handler for Basic09, and it works. I 
tested it myself. When you run it, use another window to type send -<signal> 
<proc> where signal is the number and proc is the process.

Wayne

example:

PROCEDURE testsig
TYPE REG=cc,a,b,dp:BYTE; x,y,u:INTEGER
DIM regs:REG
DIM sigHandler(3),callCode,signal:BYTE
sigHandler(1):=231
sigHandler(2):=196
sigHandler(3):=59
callCode:=$09
regs.x:=ADDR(sigHandler)
regs.u:=ADDR(signal)
RUN SysCall(callCode,regs)
LOOP
EXITIF signal=3 THEN
ENDEXIT
IF signal>0 THEN
PRINT signal
signal:=0
ENDIF
ENDLOOP
END

----- Original Message ----- 
From: "Bob Devries" <devries.bob at gmail.com>
To: "CoCoList for Color Computer Enthusiasts" <coco at maltedmedia.com>
Sent: Saturday, January 23, 2010 9:20 PM
Subject: Re: [Coco] signal/intercept routine in Basic09


> I'm wondering if the ON ERROR GOTO in Basic09 only handles errors 
> generated by the Basic09 interpreter, but not those which come from an 
> external source?
>
> --
> Besides a mathematical inclination, an exceptionally good mastery of one's 
> native tongue is the most vital asset of a competent programmer.
>
> Edsger W.Dijkstra, 18 June 1975
>
> ----- Original Message ----- 
> From: "Aaron Wolfe" <aawolfe at gmail.com>
> To: "CoCoList for Color Computer Enthusiasts" <coco at maltedmedia.com>
> Sent: Sunday, January 24, 2010 3:19 PM
> Subject: Re: [Coco] signal/intercept routine in Basic09
>
>
> Are signals really equivalent to errors?  That doesn't seem right.  Or
> is this a Basic09 thing?
> Signals can happen for many "non error" reasons, for instance a Wake
> signal often means a very normal, non error condition.  In the case at
> hand, the  "other end hung up" signal is sort of an error I guess, but
> it's not an OS9 error like read or write errors are.
>
> as I understand it, os9 'sends' a signal by calling the routine at the
> address stored in the P$SigVec field of the process descriptor.  Does
> Basic09 automatically put a routine here that turns a signal into an
> error that will trip the ON ERROR of a running program?
>
>
> On Sat, Jan 23, 2010 at 11:02 PM, Wayne Campbell <asa.rand at gmail.com> 
> wrote:
>> Apparently, ON ERROR GOTO doesn't like 4. I opened a window, ran a test 
>> prog
>> that just ran a loop and reacted to ON ERROR GOTO. When I sent the signal 
>> 4
>> to the process from the other window (used send -1 <proc>), Basic09 
>> dropped
>> into debug instead of going thru the error trap.
>>
>> Wayne
>>
>> ----- Original Message ----- From: "Christopher Hawks" <chawks at dls.net>
>> To: "CoCoList for Color Computer Enthusiasts" <coco at maltedmedia.com>
>> Sent: Saturday, January 23, 2010 7:36 PM
>> Subject: Re: [Coco] signal/intercept routine in Basic09
>>
>>
>>> Wayne Campbell said the following on 01/23/2010 07:59 PM:
>>>>
>>>> This sounds like a modification to the way drivewire sends signals?
>>>
>>> Standard OS9 signaling. Drivewire sends a Hangup signal.
>>>
>>> lda P$ID,x Process to send to
>>> ldb #S$HUP Signal to send ( 4 )
>>> os9 F$Send doit
>>>
>>>> ----- Original Message ----- From: "Robert Gault"
>>>> <robert.gault at worldnet.att.net>
>>>> To: "CoCoList for Color Computer Enthusiasts" <coco at maltedmedia.com>
>>>> Sent: Saturday, January 23, 2010 5:52 PM
>>>> Subject: Re: [Coco] signal/intercept routine in Basic09
>>>>
>>>>
>>>>> Aaron Wolfe wrote:
>>>>>>
>>>>>> It's probably worth noting that the "port closed" signal is not a 
>>>>>> part
>>>>>> of standard OS-9, it is a feature of the DriveWire additions we're
>>>>>> working on. The signal's value is 4. It is sent to a process when
>>>>>> the remote end of a TCPIP connection closes.
>>>>>>
>>>>>
>>>>> For what it is worth, Basic09 would trap the error 4.
>>>>> ON ERROR GOTO 100
>>>>> ERROR 4
>>>>> END
>>>>> 100 PRINT"The error was caught."
>>>>>
>>>>> When this is run, the message is printed. Now the manual indicates 
>>>>> that
>>>>> there is no real difference between signals and errors. Errors are 
>>>>> just
>>>>> specific signals. So, if the signal to be caught is coming from 
>>>>> Drivewire,
>>>>> it does not seem to be getting through to Basic09. That's assuming 
>>>>> error
>>>>> trapping as above is being used.
>>>>>
>>>>> It may mean that using syscall to set up an intercept may not work
>>>>> either.
>>>>>
>>>>> --
>>>>> Coco mailing list
>>>>> Coco at maltedmedia.com
>>>>> http://five.pairlist.net/mailman/listinfo/coco
>>>>
>>>>
>>>> --
>>>> Coco mailing list
>>>> Coco at maltedmedia.com
>>>> http://five.pairlist.net/mailman/listinfo/coco
>>>>
>>>
>>>
>>> --
>>> Christopher R. Hawks
>>> HAWKSoft
>>> ---------------------------------------------------------
>>> "The reasonable man adapts himself to the world: the unreasonable one
>>> persists in trying to adapt the world to himself. Therefore all progress
>>> depends on the unreasonable man."
>>> -- George Bernard Shaw
>>>
>>> --
>>> Coco mailing list
>>> Coco at maltedmedia.com
>>> http://five.pairlist.net/mailman/listinfo/coco
>>
>>
>> --
>> Coco mailing list
>> Coco at maltedmedia.com
>> http://five.pairlist.net/mailman/listinfo/coco
>>
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco