Files of this type and auxiliary type contain application programs for the Apple IIgs.
Changes since December 1991: Broadened the definition auxiliary type bit 1 to mean the application can handle getting control with the Super Hi-Res screen on.
Files of type $B3 contain GS/OS application programs. These files contain program code in Object Module Format (OMF) that is loaded by the System Loader or ExpressLoad at an address and is then executed in a documented environment.
The environment and constraints for application programs are documented in GS/OS Reference; all developers creating file of type $B3 should be familiar with this material. OMF is documented in GS/OS Reference and the APW Reference Manual.
The auxiliary type for $B3 files is now defined to indicate properties of the program contained within the file. Other parts of the system may use this information to properly control the environment for the program:
Note: If an application has the Desktop Application bit set, it should be prepared to get control with either the text or the Super Hi-Res screen visible. For example, if some error prevents the application from using the desktop tools, it may be necessary to call GrafOff before the user can read error messages displayed on the text screen although GrafOff is a QuickDraw II call, it's OK to call GrafOff even if QuickDraw II is not active).
If an application does not have the Desktop Application bit set (or does not even have a $DBxx auxiliary type), the system software reserves the right to force the text screen to be visible if QuickDraw II is not started. Do not assume that a Quit call from one application to another (with QuickDraw II not started) will leave the Super Hi-Res screen visible.
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