krb5_kt_get_full_name
kret = krb5_kt_get_full_name(context, _gsskrb5_keytab, &name);
kret = krb5_kt_get_full_name(context, cred->keytab, &name);
kret = krb5_kt_get_full_name(context, keytab, &str);
ret = krb5_kt_get_full_name(context, keytab, &str);
krb5_kt_get_full_name (context, id, &kt_name);
ret = krb5_kt_get_full_name(context, id, &name);
krb5_kt_get_full_name (
ret = krb5_kt_get_full_name(context, keytab, &str);