Submitted by Anonymous on Wed, 10/09/2002 - 13:16. Developers
When I grab the scrollbar (vertical) on my scrolled list and either try to move it all the way to the bottom or all the way to the top, it causes the application to crash with a Bus Error. Using the mouse and moving the arrows at the top or bottom of the scroll bar seem to work just fine for moving one item at a time?
Is this a bug or is there some resource I need to set to allow it to function in the way I`ve described?
I`m using Motif 1.2.4 X11R5 on Solaris 2.5.1.
Thanks!
I have a stack
0xef2ad234 in XtCallCallbackList()
#1 0xef40543c in ScrollCallback()
#2 0xef2d20fc in HandleActions()
#3 0xef2d26e4 in HandleSimpleState()
#4 0xef2d2c90 in _XtTranslateEvent()
#5 0xef2b5cb4 in DispatchEvent()
#6 0xef2b63d8 in DecideToDispatch()
#7 0xef2b64b8 in DispatchEvent()
#8 0xef2b67d4 in XtAppMainLoop()
#9 0x13f00 in main(argc = 1, argv = 0xefffd964) at SitMap.cpp 218
Interestingly enough, I went back to old code that was browse_select and the problem doesn`t occur at all. And in extended select, if I use the arrows to increment or decrement it doesn`t occur.
I tried putting in a call back to see what the scroll bar was doing (as per Volume 6A example) but that only gave me segmentation faults and more problems so I took them out!
I guess you forgot to set *noCoreDumps True .
In any case, this error seems to be within Xt but it almost certainly an application problem, and probably one in which your application is either giving bad data to XmList or stomping on memory that Xt uses.
Check that lists that should be NULL-terminated are, that counts are correct for the number of items in a list, and that the XmString values are surely valid.
You can also use a debugged libXt (one may already be on your system) and use AcquaProva or Purify to check for out-of-bounds memory-writes.