Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!trwind!venice!press
From: press@venice.SEDD.TRW.COM (Barry Press)
Newsgroups: comp.windows.ms
Subject: Re: WARNING! Serious Memory Leak in MSWindows3.0 - BUG!
Keywords: windows microsoft memory leak BUG BUG BUG
Message-ID: <1119@venice.SEDD.TRW.COM>
Date: 4 Jun 91 21:51:31 GMT
References: <1346@cthulhuControl.COM>
Reply-To: press@venice.sedd.trw.com (Barry Press)
Organization: TRW Systems Engineering & Development Division, Redondo Beach, CA
Lines: 26

<Long message about theories where memory is going on first invocation deleted>

In programming a number of winapps, I can tell you from experience that the
following does occur.  If this is indeed responsible for what you're seeing,
it's due to a change from win2 to win3 that has not been reflected in all
applications.

When an application starts, it registers one or more window classes, and
then creates windows of those classes.  Under win2, you didn't have to do
anything special to cause the registrations to go away when your application
exited.  Under win3, I have seen that applications I've written that do nothing
about this issue leave 3 or 4 (as I recall) memory blocks allocated.  If,
just before the WinMain function returns I do a call to the (new for win3)
UnregisterClass function, then those blocks go away.

I don't recall how big the blocks were, so can't be sure this is what you're
seeing.  If it is, however, then the problem is not win3 per se, but a
change from win2 to win3 not being understood by all developers.  This
would be true even for new winapps under win3 -- if you don't unregister
the window classes, you'll leave allocated memory.  And yes, it only happens
on the first execution, since after that the class is either not registered
again or else the registration attempt fails (silently, I presume, on the
part of the application).

-- 
Barry Press                                 Internet: press@venice.sedd.trw.com