[comp.sys.mac] Dangerous bug in Flex screensaver

eacj@batcomputer.tn.cornell.edu (Julian Vrieslander) (08/27/88)

I recently discovered a rather serious side effect produced by the "Flex"
screen saver.  With *each* activation of the Flex display, a WindowRecord
is added to the WindowList of the currently running application.  Worse
yet, the WindowRecords are not disposed - repeated activations of Flex
result in additional dead WindowRecords in the list.

Each WindowRecord only eats up 156 bytes, so you would have to invoke
Flex quite a few times before the amount of wasted memory is significant.
What is more dangerous is that these WindowRecords could cause heap
fragmentation, or worse yet, break applications that scan the WindowList.

I have reported the problem to Ben Haller, the author of Flex (I posted it
to the network for him).  Until he comes up with a fixed version, I would
recommend not using Flex.  The (buggy) one that I tested was version 3.1.
Please do not send me mail requesting  a fixed version - write to Ben
at 32 Deerhaven Rd., Ithaca, NY 14853.
-- 
Julian Vrieslander     "Don't rush me... you'll get a rotten miracle."
Neurobiology & Behavior, W250 Mudd Hall, Cornell University, Ithaca NY 14853    
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