[Coco] gray hair syndrome

Roger Taylor rtaylor at bayou.com
Sun Dec 28 21:46:26 EST 2003


Pull one hair, and 2 more grow back.  This is what happened when I started 
fixing a few bugs in Portal-9 that only crashed some people's machines.

When I debug, I don't quit until something works.  So I ended up 
discovering a bug in Windows 98 instead of Portal-9.

Here is the line:

SendMessage(hWnd_Tabs, TCM_GETROWCOUNT, 0, 0);

It is that exact line and only that line that causes a memory access 
violation on some Win98 machines.  What's happening?  Some versions of 
Windows 98 cannot handle the MULTILINE tab control style.  This is the 
style that spreads the tabs downwards like a stack of folders instead of 
the annoying horizontal-only style which you have to scroll through.

For some reason, their config/version of Windows 98 cannot process the 
TCM_GETROWCOUNT message.  This is two machines, so I assume others have the 
same problem.  After I changed the tab control style to SINGLELINE and did 
away with checking how many rows of tabs are present (and assuming only 1), 
Portal-9 did not crash on those Win98 machines.  *My* old-as-dirt copy of 
Windows 98SE has no probem with multi-line tab controls nor the call for 
returning how many rows of tabs are present.  Go figure!

So, I have no choice but to use the single-line tab control format for now 
until I figure out a way to get the "stubborn?" 98 machines to work with it 
without crashing.

It's nothing major, but you'll be able to see the difference in tab styles 
when you open a large project like Projector-3.

Those who are expecting a CD package in the mail will still get it, but it 
will probably be a week.  It might take a night or two more to make sure 
everything is back in order.

----------
Roger Taylor






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