if(getFileSystem().isReadOnly()) { throw new ReadOnlyFileSystemException("addFile in readonly filesystem"); }
	public FSEntry addFile(String name) throws IOException {		name = name.trim();		String shortName = generateShortNameFor(name);		FatDirEntry realEntry = new FatDirEntry(this, splitName(shortName), splitExt(shortName));		LfnEntry entry = new LfnEntry(this, realEntry, name);		shortNameIndex.put(shortName, entry);		longFileNameIndex.put(name, entry);		setDirty();		flush();		return entry;	}