kdestroy(1) - remove one credential or destroy the current ticket file 
-credential=principal
        remove principal from the credential cache if it exists.
 
-c cachefile
 
-cache=cachefile
        The cache file to remove.
 
-A
 
--all   remove all credential caches.
 
--no-unlog
        Do not remove AFS tokens.
 
--no-delete-v4
        Do not remove v4 tickets.