Path: utzoo!utgpu!utstat!jarvis.csri.toronto.edu!mailrus!nrl-cmf!ames!amdahl!oliveb!amiga!jimm
From: jimm@amiga.UUCP (Jim Mackraz)
Newsgroups: comp.sys.amiga
Subject: Re: Window To Front bug
Message-ID: <3370@amiga.UUCP>
Date: 21 Feb 89 19:43:13 GMT
References: <8902161959.AA19279@postgres.Berkeley.EDU>
Reply-To: jimm@cloyd.UUCP (Jim Mackraz)
Organization: Commodore-Amiga Inc, Los Gatos CA
Lines: 44

In article <8902161959.AA19279@postgres.Berkeley.EDU> dillon@POSTGRES.BERKELEY.EDU (Matt Dillon) writes:
):Could someone refresh us on what the window to front bug is/was? 
)
)	Certainly.  The window-to-front bug (WindowToFront()/WindowToBack()) is
)some kind of timing-window bug inside intuition or in the workbench-intuition
)interaction.  It appears to crop up when programs WindowToFront()/Back() other
)program's windows.

That one is a deadly embrace by Workbench holding the layers locks 
--necessary to drag an icon across other people's windows--until
it hears an upclick, and Intuition demanding the layers locks to pop
the window to front before it processes any more input.

There are other operations which can cause the deadlock (such as opening a
window), but I am unaware of any cases which don't involve WB dragging an
icon.  I'd love to hear of any, of course, ... with some details ;^)

)	It crops up even more often when dmouse and the workbench (loadwb) are 
)running and dmouse is used to bring one or the workbench's windows to the 
)front.  The problem has been linked to the workbench attempting to highlight
)an icon and dmouse attempting to WindowToFront() at the same time.  Since both
)use a click/double-click to accomlish their respective actions the case comes 
)up often.

)	To combat the problem, DMouse uses LayerToFront()/LayerToBack() by 
)default.  Unfortunately, while this fixes the lock-up bug, it doesn't work 
)well with SIMPLE_REFRESH or SUPER_BITMAP windows.  The -w1 option can be used
)to switch back to WindowToFront()/WindowToBack().  One can also combat the
)problem by setting the number of clicks required to bring the window to the
)front > 1.

LayerToFront?  Hmm, you weird.  I expect this to be all fixed up for V1.4,
probably by deferring the WindowToFront until the user is done dragging the
icon (lets go of the button).  Probably need to think of some way to keep
multiple WindowToFront requests from queuing up.

)							-Matt

	jimm
-- 
Jim Mackraz, I and I Computing	   	"Like you said when we crawled down
{cbmvax,well,oliveb}!amiga!jimm          from the trees: We're in transition."
							- Gang of Four
Opinions are my own.  Comments are not to be taken as Commodore official policy.