83Plus:BCALLs:52F6
From WikiTI
Synopsis
Unofficial Name: SetAppRestrictions
BCALL Address: 52F6
Minimum OS Version: 2.40
Enable specified "TestGuard 2" app/program restrictions.
Inputs
- A = 0: disable app by name
- OP1 = name of app to disable
- A = 1: disable all apps
- A = 2: disable programs
- A = 3: disable programs and all apps
- A = 4: set permission bitmap
- OP3 (14 bytes) = new bitmap to be ANDed with current bitmap
Outputs
- Carry set if A = 0 and the requested app does not exist
- Otherwise, carry reset, regardless of the effect or lack thereof
Destroys
- AF, BC, DE, HL
- OP1-OP2, ramCode, probably other areas
Comments
Note that this routine is cannot remove restrictions, only create them.
The permission bitmap, used by the A = 4 option, is fourteen bytes and is arranged as follows:
- Byte 0, bit 0 is reset to disable execution and editing of both BASIC and assembly programs in the OS.
- The remaining bits of byte 0 appear to be unused, but might be used in the future for other global permission states.
- Byte a, bit b (a > 0) is reset to disable execution of the application with base page 8a+b. (In other words, the pages are given in "memory order," rather than "installation order" as with the app presence bitmap.)
- The last 8 bytes are unused on the 84+ BE (but the corresponding bytes of OP3 are still copied to the certificate.)
Remember that you can clear all restrictions by receiving any file over the link, or by manually sending a file.
