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From: rich@wiley.uucp (Rich Messenger)
Newsgroups: comp.windows.ms.programmer
Subject: Solution to BC++ Petzold problem, and mild bug report
Message-ID: <2828D392.40DD@wilbur.coyote.trw.com>
Date: 9 May 91 04:44:02 GMT
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Organization: TRW Inc., Redondo Beach, CA
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I recently posted a question about wierd behavior trying to get
Petzold's first sample program from _Programming Windows_ to run under
BC++.  Although there were no reposnses from this news group, I
eventually tracked down the problem and thought I might be of general
interest to other BC++ users.

(1) When you are compiling as C++, you *cannot* use the EXPORTS section
in the .DEF file, since the name is mangled by C++ before the linker
ever sees it.  This tidbit is not mentioned in the documentation.

(2) You can use "smart callbacks" and thigs work great as long as
you're not writing a DLL or using the huge memory model.

(3) You can tag exportable functions with "_export".  You *must* put
this keyword in both the function declaration and function definition.
MILD BUG: BC++ does not complain if you declare the function without
_export, and define it with _export; it simply exhibits wierd behavior
on execution.

Example of bad code which BC++ does not complain about but which
causes erroneous execution:

	long FAR PASCAL WndProc(HWND, WORD, WORD, LONG);

	...definition of WinMain()...

	long FAR PASCAL _export WndProc(HWND hwnd, ...

Hope this helps the next guy who naively tries to type in the Petzold
examples straight from the book but uses C++ instead of C.
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