Converting PB/DOS to PB/CC

[Tom Bohon]

I have been asked to look into converting a PB DOS program to the
PBCC compiler. Haven't really had time to do much with it so far
but I was wondering if anyone can 'clue me in' on problems I'm
going to face when I start?

Thanks in advance.

Tom

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[Mel Bishop]

See that this is your first post. Welcome to the board.

In as far as syntax goes, with some exceptions, it's pretty
much a straight conversion.

The only main thing you have to do is "wrap" your main segment
in FUNCTION PBMAIN() with a terminating END FUNCTION.

In PB/DOS, you can use variables on-the-fly as needed. In CC,
you have to DECLARE them as LONG, STRING, INTEGER, etc. before
you can use them.

There are a few other bells-n-whistles you have to take into
consideration but basically, that's pretty much it.

You might want to browse the source code forum and check out
some CC examples.

Oh, almost forgot to add: You better turn your speakers off or
get used to that "Ka-Chung" critical error notice CC will give
you when you make a mistake.

Just out of idle curosity, what kind of program is it that you
have been asked to convert?
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[This message has been edited by Mel Bishop (edited August 06, 2006).]

[Fred Buffington]

Mel, isn't it be true that if the pbdos program
had a DEFINT A-Z (for example) and the PBCC PROGRAM
also had the same DEFxxx A-Z in it without a DIM ALL that variables
would default to that type as in pbdos. Otherwise, what
is the use of a DEFINT,DEFLNG etc. Also without
the DIM ALL other variables can be done 'on the fly' as long as the
variable ends with the correct symbol ($,#,!, etc) .

BTW: I do believe that DIM ALL is the way to go since it
can avoid nasty spelling error problems that may be
hard to debug sometimes.

The following 2 programs have the same result except as Mel
notes below the pbcc program without a waitkey or inkey$ loop
will close the window when ended.

TryPB32
------

  DEFINT A-Z
  A=100
  PRINT A

PBCC
----

  DEFINT A-Z
  FUNCTION PBMAIN() AS LONG
    A=100
    PRINT A
  END FUNCTION

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[This message has been edited by Fred Buffington (edited August 06, 2006).]

[Mark Hunter]

Two things come first to mind:

A. The file for a PBDOS program contains the main program together with any procedures it calls.

B. In PBCC everything must be a procedure. Where then does the program start? It always starts by executing the function named PBMAIN (or WINMAIN).

So to convert from PBDOS to PBCC you must wrap your main code inside
FUNCTION PBMAIN [or WINMAIN]
...
END FUNCTION

A. PBDOS: Printed output goes to the monitor screen and unless explicitly erased it persists after the program ends.

B. PBCC: Printed output goes to the console window and that window automatically closes when the program ends.

So in your conversion you may want to put the PBCC instruction WAITKEY$, which waits for a keypress, before the program ends.

For more, see the Help file under
Programming Reference / Upgrading to PBCC

If you don’t own PBCC already, the Help file is online at www.powerbasic.com/support/help/pbcc/wf_njs.htm


[This message has been edited by Mark Hunter (edited August 06, 2006).]

[Michael Mattias]

Alan Earnshaw once suggestion one should be begin a PB/DOS=> PB/Windows(any) conversion by changing the MS-DOS program to work in the "all executable code must be within a procedure" format.

That is, the DOS program should look like..

$COMPILE EXE

  CALL Main

  END

FUNCTION Main 
...

I still think that is a great idea. Make the changes working in the environment in which you are most comfortable.

Also quickly identifies "variable scope" isssues which must be resolved anyway.

MCM

[Mark Hunter]

Third thing that comes to mind ...

A. PBDOS: You use the keyword SHARE to indicate that the scope of a variable goes beyond a procedure, and you can use it within or outside procedures.

B. PBCC: You use the keyword GLOBAL instead, you (should) use it outside any procedure, and it applies to all procedures.

[Knuth Konrad]

Appendix B of the PB/CC help file, called "Upgrading from DOS" might also be worth a look.

Knuth

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