Hello Andreas!

In a msg originally to Andrew Belov, Andreas Mueller said:

 AB>> IBM never will change the situation with SIQ. Instead, they provide a
 AB>> patch in Warp 4 (and Warp 3, beginning with Fixpak #17) that can help
 AB>> in some (very few) situations when the user interface locks. It's not
 AB>> a solution at all but I think the reason for it is the compatibility:
 AB>> some applications may malfunction if the SIQ will be replaced with
 AB>> multiple queues. Fixpak #17 already broke the functionality of some
 AB>> apps, including MS Word for OS/2 and File Manager from OS/2 v 1.x.

 AM> Do you any details about the patch you mentioned?

Well, it's not exactly a patch but a new CONFIG.SYS option. It's briefly
described in FixPak release notes. According to the documentation,

SET PM_ASYNC_FOCUS_CHANGE=ON 2000

will force OS/2 to switch the focus from a message that monopolizes its
message queue in two seconds (after a user action?)

 AM> We use a portable GUI library (StarView) that produces memory leaks with
 AM> exactly these OS/2 versions. As StarView is no longer supported we're
 AM> forced to track down this problem by ourselfs.

[...]
 AM> Did the patch in Warp4/Warp3FP17 change anything that the WM_PAINT
 AM> message is involved with?

Unfortunately I'm not an IBM engineer to be well informed about PMMERGE
internals, however it seems to result from the message processing.
Somewhere in the Internet I've found an article saying that the PM message
queue patch was designed by one of enthusiastic programmers and was _not_
honored by IBM. Later on, after an exhaustive testing, IBM released this
fixpak.

In addition to the PM_ASYNC_FOCUS_CHANGE, FixPak 17 introduced some
internal changes in the kernel (notably some newer DevHlp stubs) that make
the Warp 3 kernel more alike Warp 4 kernel. Beginning with this FixPak,
some multitasking concepts were reviewed too.

I think it's possible to find some articles regarding internal changes in
FixPak 17, the question is where.

                                                     Bye.

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