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Inside Macintosh: More Macintosh Toolbox /

Chapter 1 - Resource Manager / Resource Manager Reference

Resource Manager Routines / Getting Resource Sizes

GetResourceSizeOnDisk

You can use the GetResourceSizeOnDisk function to get the exact size of a resource. The GetResourceSizeOnDisk function is also available as the SizeResource function.

FUNCTION GetResourceSizeOnDisk (theResource: Handle): LongInt;

theResource

A handle to a resource.

DESCRIPTION

Given a handle to a resource, the GetResourceSizeOnDisk function checks the resource on disk (not in memory) and returns its exact size, in bytes. If the handle isn't a handle to a valid resource, GetResourceSizeOnDisk returns -1, and ResError returns the result code resNotFound.

You can call GetResourceSizeOnDisk before reading a resource into memory to make sure there's enough memory available to do so successfully.

RESULT CODES

noErr	0	No error
resNotFound	-192	Resource not found

SEE ALSO

To check for errors, call the ResError function as described on page 1-47.