void InitKeys ()
{
if (initKeys)
return;
CreateKeyMap ();
rootmap = new ByteMatcher ();
foreach (TermInfoStrings tis in UsedKeys)
AddStringMapping (tis);
rootmap.AddMapping (TermInfoStrings.KeyBackspace, new byte [] { control_characters [ControlCharacters.Erase] });
rootmap.Sort ();
initKeys = true;
}