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Inside Macintosh: Memory /

Chapter 3 - Virtual Memory Manager / Virtual Memory Manager Reference

Routines / Virtual Memory Debugger Support Routines

GetPageState

To obtain the state of a page of logical memory, use the GetPageState function.

FUNCTION GetPageState (address: UNIV Ptr): PageState;

address

An address in the page whose state you want to determine.

DESCRIPTION

The GetPageState function returns the page state of the page containing the address passed in the address parameter. The returned value is one of these constants:

TYPE PageState = Integer;

CONST
   kPageInMemory  = 0;           {page is in RAM}
   kPageOnDisk    = 1;           {page is on disk}
   kNotPaged      = 2;           {address is not paged}

ASSEMBLY-LANGUAGE INFORMATION

The trap macro and routine selector for the GetPageState function are

Trap macro	Selector
_DebugUtil	$0004

The registers on entry and exit for this routine are

Registers on entry
A0	Address in the page whose state is to be determined
D0	Selector code

Registers on exit
D0	Page state