Chapter 6 Function Descriptions

AZPtrToHand/DSPtrToHand

MgErr AZPtrToHand(p, hp, size);

MgErr DSPtrToHand(p, hp, size);

Purpose

Creates a new handle of size bytes and copies size bytes from the address referenced by p to the handle.

Parameters

Name	Type	Description
p	UPtr	Source of data you want to copy to the handle
		pointed to by hp.
hp	UHandle	Pointer to handle you want to duplicate. A
		pointer to the resulting handle is returned in
		this parameter. Refer to the Pointers as
		Parameters section in Chapter 3, CINs, for
		more information about using this parameter.
size	int32	Number of bytes to copy from p to the new
		handle.

Return Value

mgErr, which can contain the following errors:

NoErr	No error.
MFullErr	Not enough memory to perform the operation.

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Chapter 6 Function Descriptions

AZPtrToXHand/DSPtrToXHand

MgErr AZPtrToXHand(p, h, size);

MgErr DSPtrToXHand(p, h, size);

Purpose

Copies size bytes from the address referenced by p to the existing handle h, resizing h, if necessary, to hold the results.

Parameters

Name	Type	Description
p	UPtr	Source of data you want to copy to the handle
		h.
h	UHandle	Destination handle.
size	int32	Number of bytes to copy from p to the
		existing handle.

Return Value

mgErr, which can contain the following errors:

NoErr	No error.
MFullErr	Not enough memory to perform the operation.
mZoneErr	Handle or pointer not in specified zone.

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Chapter 6 Function Descriptions

AZRecoverHandle/DSRecoverHandle

UHandle AZRecoverHandle(p);

UHandle DSRecoverHandle(p);

Purpose

Given a pointer to a block of memory that was originally declared as a handle, this function returns a handle to the block of memory.

This function is useful when you have the address of a block of memory that you know is a handle, and you need to get a true handle to the block of memory.

Parameters

Name	Type	Description
p	UPtr	Pointer to a relocatable block of memory.

Return Value

A handle to the block of memory to which p refers. If an error occurs, this function returns

NULL.

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Chapter 6 Function Descriptions

AZSetHandleSize/DSSetHandleSize

MgErr AZSetHandleSize(h, size);

MgErr DSSetHandleSize(h, size);

Purpose

Changes the size of the block of memory referenced by the specified handle.

While LabVIEW arrays are stored in DS handles, do not use this function to resize array handles. Many platforms have memory alignment requirements that make it difficult to determine the correct size for the resulting array. Instead, use either NumericArrayResize or SetCINArraySize, described in the Resizing Arrays and Strings section in Chapter 4, Programming Issues for CINs. Do not use these functions on a locked handle.

Parameters

Name	Type	Description
h	UHandle	Handle you want to resize.
size	int32	New size, in bytes, of the handle.

Return Value

mgErr, which can contain the following errors:

NoErr	No error.
MFullErr	Not enough memory to perform the operation.
mZoneErr	Handle or pointer not in specified zone.

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