public void Save()
{
try {
if (path == null)
throw new Exception ("Path not set");
string cat_file = System.IO.Path.Combine (path, ".catalog.xml");
XmlSerializer serializer = new XmlSerializer (typeof (Catalog));
using (FileStream fs = File.Create (cat_file))
serializer.Serialize (fs, this);
} catch (Exception e) {
Console.Error.WriteLine ("Error saving settings: " + e);
}
}