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QDStartup masterSCB bits meaning

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Enrico

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Mar 30, 2022, 8:37:48 AM3/30/22
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I'm struggling to find out the meaning of bit 8 of the masterSCB parameter in a QDStartUp Toolbox call.

I see that a lot of GS apps use to set this bit high.

According to the Toolbox documentation volume 3, this bit should be Reserved!?

masterSCB:
bit 15 -> fUseShadowing
bit 14 -> fFastPortAware
bits 8-13 -> Reserved
bits 0-7 -> SCB

Enrico

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Mar 30, 2022, 8:41:44 AM3/30/22
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Ok, it seems stupid to reply to my own question, but I just found the answer to it on "Apple IIGS Toolbox Changes
for System Software 6.0 (ERS version 2.5)" by David A. Lyons (February 26, 1992)

"Added a QDStartUp MasterSCB bit (value $0100, bit 8) that causes the screen not to
be cleared if it is already being displayed. StartUpTools uses this to avoid wiping
the screen first to black and then to the desktop pattern, when the Window Manager is
also being started up."
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