@Override
	public final T getReadOnlyObject(FolderItem item, int version, boolean okToUpgrade,
			Object consumer, TaskMonitor monitor)
			throws IOException, VersionException, CancelledException {
		if (!okToUpgrade) {
			throw new UnsupportedOperationException("okToUpgrade must be true for link-file");
		}
		return getObject(item, version, consumer, monitor, false);
	}
Create a link file using the specified URL
@param ghidraUrl link URL (must be a Ghidra URL - see {@link GhidraURL}).
@param fs filesystem where link file should be created 
@param folderPath folder path which should contain link file
@param linkFilename link filename
@throws IOException if an IO error occurs
@throws InvalidNameException if invalid folderPath or linkFilename specified
Ghidra/Framework/Project/src/main/java/ghidra/framework/data/LinkHandler.java