SizeResource
Handle rHandle ; a handle to a valid resource returns the size, in bytes, of the resource (-1= error)
This procedure returns the physical size of a specified resource. It is useful
to check this to be sure there is enough memory to hold a resource.
rHandle is a resource handle. It is a handle obtained via GetResource, Returns: a 32-bit long integer; the size of the resource, in bytes; the amount of memory needed if the resource is loaded. A return value of -1
indicates an error and ResError will return a code of resNotFound.
Notes: This function reads from disk in order to return the exact size of the
resource. The 128K ROMs support the more efficient function,
MaxSizeRsrc, which gets an approximate size of the resource without reading it from the disk.