Legacy Document

Inside Macintosh: Memory /

Chapter 2 - Memory Manager / Memory Manager Reference

Memory Manager Routines / Manipulating Blocks of Memory

PtrToXHand

To copy data referenced by a pointer to an already existing relocatable block, use the PtrToXHand function.

FUNCTION PtrToXHand (srcPtr: Ptr; dstHndl: Handle; size: LongInt):
                     OSErr;

srcPtr

The address of the first byte to copy.

dstHndl

A handle to an already existing relocatable block to which to copy size bytes, beginning at srcPtr.

size

The number of bytes to copy.

DESCRIPTION

The PtrToXHand function makes the existing handle, specified by dstHndl, a handle to a copy of the number of bytes specified by the size parameter, beginning at the location specified by srcPtr.

SPECIAL CONSIDERATIONS

Because PtrToXHand affects memory, you should not call it at interrupt time.

ASSEMBLY-LANGUAGE INFORMATION

The registers on entry and exit for PtrToXHand are

Registers on entry
A0	Pointer to source
A1	Handle to destination
D0	Number of bytes to copy

Registers on exit
A0	Handle to destination
D0	Result code

RESULT CODES

noErr	0	No error
memFullErr	-108	Not enough memory
nilHandleErr	-109	NIL master pointer
memWZErr	-111	Attempt to operate on a free block