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APPLE II DEVELOPMENT FORUM CONFERENCE LOG
Tuesday, August 21, 1990  10:00 p.m. Eastern Time
Topic:  BASIC Programming
Forum Leader:  Dave Sugar  (AFL Dyfet)

AFL Dyfet  Okay, good evening and welcome to the Apple II Development Forum. 
           Tonight our
AFL Dyfet  topic centers on programming in Basic, and we will begin
           shortly...
AFL Dyfet  Okay, we will be using protocol starting now.  If you wish to ask
           a question,
AFL Dyfet  enter a '?' on a line by itself, and if you wish to comment on the
           current
AFL Dyfet  question being discussed, enter a '!' on a line by itself.  The
           floor is now
AFL Dyfet  open for questions.
AFL Dyfet  Go ahead, AFC TAP, you have the floor now.
AFC TAP    thanks... simple one...
AFC TAP    will th new basic system fix the bug in the chain code??
AFC TAP    ga
AFL Dyfet  Go ahead Dave...
Dave Lyons What bug?  I thought that was fixed in 1.4, but maybe my brain is
           toast.
AFC TAP    ok, I run 1.3 and it crashes on accasion during chains...
AFA Gary J I think Dave is correct.
Dave Lyons Crashes??  Ouch.  Are you talking about a bug that's been
           discussed
Dave Lyons in A2-Central a lot, or something else?
AFL Dyfet  That old bug was squashed in 1.4 :)...I recall a work-around I had
           to do for it
AFL Dyfet  in the old days when I was programming UBBS :)...Okay, GA
           Rosen...
RosenNeil  isnt 1.3 the one that had the bug with BLOAD and BSAVE..if so
           trash it!
AFC TAP    I heard it was the variable squashing or somethiong like that...
Dave Lyons (Yes, 1.3 had a bad BLOAD.  But that's the only thing fixed from
           1.3 to 1.4; the CHAIN stuff
Dave Lyons should be okay in 1.3)
AFC TAP    thanks...
AFL Dyfet  Go ahead Joey
AFA JoeyS  Yeah... I've got the patch laying around somewhere, Scott; the BI
           that comes w/
AFA JoeyS  EBBS has the patch installed... compare it to a normal
           BASIC.SYSTEM to see 
AFA JoeyS  where the changes are... <shrug>  :) GA
Dave Lyons (BTW, P8 Technical Note #24 has the revision history for
           BASIC.SYSTEM.)
Dave Lyons (done)
AFC TAP    thanks  (ga)
AFL Dyfet  Okay, I believe Tamira has the next question/comment and the floor
           now...GA
Tamira     This has nothing to do with ADV but since all my friends are here
           I thought I would share some good 
Tamira     news before I go....As of Sept 1st you are looking at the new Head
           Innkeeper at the Red Dragon Inn and
Tamira     the writer for Lifestyles for the Phantasy Guild.....an kinda
           proud of it BTW  :D
RosenNeil  Congratulations.....
A2GS       Congrats Tam!!
AFL Dyfet  Great!!
Nuzz       good news Tamira, and well deserved
Tamira     BLUSH   thanx all
Tamira     I was just BURSTING with the news and had to tell SOMEONE!!!
AFA Gary J That's good news, Tamira!
Arc42      I've got a big Shrinkit problem, guys
Arc42      I only have one disk drive, and the Shrunk file won't fit on the
           disk with
Arc42      the unshrunk file.  Am I doomed?
AFA JoeyS  (unless you have a RAM disk large enough to hold the shrunk file,
           yes, Arc, :( 
AFL Dyfet  Okay, Joey, go ahead...
AFA JoeyS  Okay, here's a fun one: I'd like to write a configuration program
           that defines
AFA JoeyS  a series of variables in memory.  These variables, unfortunately,
           AREN'T nice
AFA JoeyS  and tidy (i.e. array format) -- just different names all over. 
           What's the 
AFA JoeyS  best way to do this??  I was thinking of storing tokenized
           assignment strings
AFA JoeyS  in a datafile and poking them into the middle of the basic
           program, but that
AFA JoeyS  seems awfully messy... any other ideas??
AFA JoeyS  GA
AFA JoeyS  LOL, no one has an answer to my question?
AFL Dyfet  You are trying to initialize an array in memory, Joey?  You could
           try to locate
AFL Dyfet  it in memory by the descriptor table and then bload what you need
           into it...
AFA JoeyS  No, it's got nothing to do with arrays.  I've got an arbitrary set
           of variable
AFA JoeyS  names (OP$, SY$, G0$, etc) that I'd like to assign with a
           configure program,
AFA JoeyS  but I don't want to have a huge set of OP$=I$:RETURN lines thrown
           into the code
AFA JoeyS  GA
AFL Dyfet  There is also the VAR filetype, which could be used to hold inital
           var values.
AFA JoeyS  Right; the results of the variable assignments will be going into
           a VAR file.
AFL Dyfet  Okay...um, what exactly is the problem you are having then...I
           think I've
AFL Dyfet  missed something in your comments...
AFA JoeyS  Okay.  I have a set of 50 or so variables that I'd like to assign
           in a BAS
AFA JoeyS  program.  I COULD do something like...
AFA JoeyS  <get variable to assign>: ON <varnum> GOSUB 1000,1100,1200,1300,
           .......
AFA JoeyS  1000 INPUT "Value of Var #1",G0$:RETURN
AFA JoeyS  And do that 50 times, but I'd rather have one general-purpose
           subroutine to
AFA JoeyS  retrieve the value of the variable... make sense?
AFL Dyfet  OH!!  I see!!  I was looking at the wrong end of the problem!
AFL Dyfet  GA AFC TAP...
AFC TAP    Joe, have you thought about using an array top build the arbitrary
           list
AFC TAP    and then pass the array to a small ML poster routine which will
           stuff the
AFC TAP    values into memeory and then you can save the VARS...
AFC TAP    use the varname in the array as a prompt if you want...
AFC TAP    ga
AFA JoeyS  Ummm... no, I hadn't thought of that... but it'd work... 'cept how
           do you
AFA JoeyS  retrieve the variable address unless the varname was passed by the
           BASIC host?
AFA JoeyS  (GA)
AFC TAP    you should know ahead of time all of the varnames right?, so pass
           a array
AFC TAP    with the varnames in a string and the value as a number, the
           poster will
AFC TAP    just go thru and locate each varname and poke the correct
           value...
AFC TAP    works for any arbitary list of names...
AFC TAP    ga
AFA JoeyS  Oh... okay, I see what you're saying... yeah, that'd work, okay...
           thanks,
AFA JoeyS  Scott :)    {S GA}
AFL Dyfet  Any further comments?
AFA JoeyS  (no one EVER likes my questions, :)
Nuzz       but we like YOU
AFA JoeyS  Awww... <blush>  Thanks, LOL
AFL Dyfet  Okay, who has the next question?
AFP TimB   What's the word on TML Basic?
Matt DTS   The word in the press release was that TML will keep selling it
           until Complete has a new version.
AFL Dyfet  TML Basic has been aquired by Complete Technology, as has TML
           Pascal.  They
AFL Dyfet  are planning to fix it up a lot before re-releasing it as Complete
           Basic.
AFP TimB   Who owns Complete?  VC?
AFL Dyfet  Yes.
AFA JoeyS  Yeah
AFA Gary J (Hmmmm I didn't notice that VCooper left).
AFA JoeyS  (he left right when I came in... coincidence?)
A2GS       VC?
AFP TimB   VC = Vince Cooper.
AFP TimB   TML has left a real sour taste in MY mouth.
A2GS       New company?
AFL Dyfet  TML had no interest in what they were doing in the IIgs market,
           period.
AFP TimB   Least I feel Mike Westerfield has some commitment to excellence.
AFL Dyfet  We will be discussing TML Pascal (Complete Pascal) with Vince
           Cooper next week,
AFL Dyfet  and that would be a good opertunity to find out about TML Basic as
           well...
AFL Dyfet  Okay, who has the next question?
AFL Dyfet  GA Gary...
AFA Gary J I don't remember if I asked this here before, I posted it over in
           Byteworks
AFA Gary J a couple of months ago.... and I think Mike lost track of it.
AFA Gary J I'm writing an assembly program (sorry, not BASIC :) that must be
           leaving 
AFA Gary J something amiss when it quits.  (Yes, I do remember asking it
           here, but I still
AFA Gary J don't know the reason :).  Anyway, after running my program, it
           causes the
AFA Gary J ORCA editor to produce an "Invalid Text Data" error when trying
           to edit a
AFA Gary J source file (ANY source file).  It hangs at that point, and I
           have to re-boot.
AFA Gary J The trouble is that it doesn't always go away on a warm re-boot. 
           I have to
AFA Gary J power off.
AFA Gary J Does anyone know what could cause such a mess?? :)
AFL Dyfet  GA Dave...
Dave Lyons Gary, it sounds like you're trashing memory semi-randomly
           somewhere.  The invalid text
Dave Lyons data message could mean you're trashing the fast-file image of
           some file in the fastfile
Dave Lyons system.
Dave Lyons The reason you would still
Dave Lyons have problems after an Apple-Ctrl-Reset is if you trashed some
           actual Memory Manager data structures.
AFA Gary J That's what I thought too (that's why I was happy to get Big
           Brother to test
AFA Gary J the situation). 
Dave Lyons The Memory Manager doesn't *really* get restarted on that kind of
           boot--remember
Dave Lyons for example that /RAM5 uses the memory manager & lives across
           Resets.
AFA Gary J A Memory Manager data structure?  Like a trashed handle?
Dave Lyons So BB didn't find any damage?  (If you always trash *used* memory,
           BB never helps!)
Dave Lyons Yeah, a trashed handle...actually a trashed "handle chain"--each
           handle points (currently) to a 20-
Dave Lyons byte structure called (at least by me!) a Master Pointer Record,
           which includes links to the
Dave Lyons previous and next handles in the chain.
AFA Gary J That's interesting.  I hadn't thought about the Memory Mangager
           re-start
AFA Gary J business.  That tells me where I need to look, in fact I can
           probably guess
AFA Gary J the problem already!  Thanks Dave.
Dave Lyons If you're ever *failing* to dereference a handle, and storing
           stuff through it as if it
Dave Lyons were a pointer, that's a *really* good way to have hard-to-find
           bugs (hard to find because you crash
Dave Lyons so quickly after it screws up, and you can't necessarily even get
           into NL or GSBug).  ga
AFA Gary J My program hasn't really crashed, just the problem with the
           editor.
AFA Gary J The ORCA editor is the only place it's showed up.  The memory
           manager
AFA Gary J business is probably it, because sometimes the ORCA editor will
           produce a 
AFA Gary J memory manager error instead of the invalid text data error.
Dave Lyons (Okay, it wouldn't *have* to crash right away...it's just more fun
           that way.)
AFA Gary J Thanks.  GA
AFL Dyfet  Okay, that Q needs some questions :)
BurgerBill Does anyone know anything about MIDISynth?
AFA JoeyS  Yuppers, Bill.
AFL Dyfet  Yes!   Avery, go ahead, you have the floor now...
Avery R C  Is there a BASIC compiler that deals with the GS/OS tools?
Avery R C  Or has that already been answered? =P
AFL Dyfet  Well, Micol Advanced Basic can perform tool calls...
AFL Dyfet  GA Dave...
Dave Lyons Okay...I haven't used them, but there are Micol Advanced BASIC and
           TML BASIC.  They can
Dave Lyons let you do GS toolbox calls, but I -believe- neither of them is as
           convenient as Pascal for
Dave Lyons doing toolbox stuff.  Especially because you want "records" for
           dealing with toolbox data
Dave Lyons structures (so you can refer to pieces of the data structures by
           name, rather than by byte offsets).
Dave Lyons ga
AFL Dyfet  (my preference is C, Dave L :)
Avery R C  Ok, I was thinking of ORCA/C anyway.
Dave Lyons (should have said "as convenient as Pascal or C"--sorry!)
Avery R C  over and out
AFL Dyfet  Okay...Who has a question then :)
BurgerBill Does anyone have information about the MIDISynth tool from
           Apple?
BurgerBill I am interested in writing music using it.
AFA JoeyS  What kind of information?
AFP TimB   Its awesome.
BurgerBill Well, how do I call it and use it in my own programs?
AFL Dyfet  GA Joey...
AFA JoeyS  Ummm... rough outline: Open sequence file.  Get instrument
           (waveform) file,
AFA JoeyS  load that in, and define the instruments to use with
           _SetInstrument calls.
AFA JoeyS  Set up your tempo, tuning table, and anything else you need
           (optional, 
AFA JoeyS  depending on your sequence)... then pass _SeqPlayer the address of
           the
AFA JoeyS  sequence data buffer.  It takes over interrupts and plays the tune
           in the
AFA JoeyS  background; you can request that the tool call you back on each
           note, on
AFA JoeyS  instrument changes, at end of song, etc etc etc.  Pretty nifty. 
           I've got some
AFA JoeyS  not-yet-finished source (for a highly rumored MIDI Synth NDA, LOL)
           that I'd
AFA JoeyS  be willing to share with ya'.   GA...
BurgerBill Thanx, I need all the help I can get! :)
AFL Dyfet  Any other comments??
AFA Gary J That sounds great, Joey!
AFA JoeyS  No sweat -- scream a reminder to me in mail if I forget, okay? :) 
           (I'm
AFA JoeyS  notorious for forgetting... uhh... everything!)
BurgerBill Well I got some info that I need, thanx alot anyways!!
AFL Dyfet  GA Nuzz
Nuzz       Just a comment on Joeys answer. That sequence PLAYS songs, writing
           them is
Nuzz       quite different
Nuzz       GA
AFA Gary J Joey missed your comment on his answer, I think :)
AFA JoeyS  I think so, yes... :-)
Nuzz       I just said that you described palying songs, not writing them
AFA JoeyS  Oh... I thought Bill asked how to play them back in his programs. 
            ....
AFA JoeyS  Errr, to be honest, I haven't tried doing a MIDI recorder, but it
           looks
AFA JoeyS  as easy as playback.
AFP TimB   My suspicion is that playback is real easy, but a fully fledged
           sequencer is a lot more diff.  Yes?
Nuzz       right Tim
AFA JoeyS  Yes, Tim -- <shrug>  depends on the amount of sophistication in
           your sequencer,
AFA JoeyS  too.

AFL Dyfet  GA Tim...
AFP TimB   Dave, Matt you know the current story on APDA and MIDISynth and a
           release date?
Dave Lyons (Nope, just watch your APDAlog...that's all I know.)
Matt DTS   Same here.
AFP TimB   Last I heard Tim Swihart was fighting with APDA on pricing.

AFL Dyfet  GA Scott
AFL Scott  Has anyone noticed problems with window paramlists generated by
           Design Master
AFL Scott  in C?
Dave Lyons (What kind of problems?)
AFL Scott  Ok... Under ORCA/C, I kept getting type conflicts in the record
           where ever a
AFL Scott  NULL was inserted... I looked at the record both in the header
           file and in the
AFL Scott  generated record and I can't see a problem.
Dave Lyons (How is NULL #defined in your program?)
AFL Scott  0x0L
Dave Lyons Hmmm...I suppose changing it to ((void *)0) would cause other
           problems?
AFL Dyfet  But perhaps more correct a representation, Dave...
AFL Scott  I can do that... I didn't do it, yet, though.  I was just fiddling
           to see if 
AFL Scott  ORCA/C could get past the error.. it did, eventually, but now it
           errors out on
AFL Scott  the DefProc. :(
AFL Scott  (which btw is a VoidProcPtr).
AFL Dyfet  Hmm...
Dave Lyons Shouldn't (void *)0 be a valid value for type void (*)() ?  I
           thought void * was supposed to be
Dave Lyons a pointer to *anything*, including a function.
AFL Scott  Looking...
AFL Scott  Your definition agrees with Harbison & Steel, Dave.   Whether it
           agrees with 
AFL Scott  Orca is up for tests after this conference.
Dave Lyons (Gee...didn't mean to kill the discussion.  Too many paentheses?
           :-)
Matt DTS   They're intimidated by you.
AFL Dyfet  NiftyLyons strikes again :)
Dave Lyons (Data types are evil.  You never have to type-cast a value in
           Nifty List. :-)

AFA Gary J Thanks for the tip on my problem, Dave.  I was wondering what
           could possibly
AFA Gary J be still messed up after a warm re-boot.
Dave Lyons (Yer welcome)
Matt DTS   Ask Dave sometime about leaving little handles around between
           reboots.
AFL Dyfet  :)
Dave Lyons (Or ask Matt.)
AFA Gary J Now's a good time :)
AFL Dyfet  Yes, it is :)
AFA Gary J What happened, Dave???
Dave Lyons I -think- this is what Matt's referring to...a good way to
           accidentally leave "permanent" handles
Dave Lyons around is to use the high word of a pointer as the memory ID!  If
           they wind up with ID $0xxx, they
Dave Lyons tend not to go away (this isn't a guaranteed system feature--it's
           just what happens today).