diff --git a/inc/Maat_command.h b/inc/Maat_command.h
index c5f4324..f22215e 100644
--- a/inc/Maat_command.h
+++ b/inc/Maat_command.h
@@ -109,9 +109,9 @@ struct Maat_group_t
 };
 struct Maat_cmd_t
 {
-	struct Maat_rule_t compile;// for MAAT_OP_DEL, only compile.config_id is necessary.
+	struct Maat_rule_t compile; // for MAAT_OP_DEL, only compile.config_id is necessary.
 	int group_num;				// for MAAT_OP_DEL, set to 0.
-	int expire_after;			//expired after $timeout$ seconds, set to 0 for never timeout.
+	int expire_after;			//expired after $expire_after$ seconds, set to 0 for never timeout.
 	int label_id;					//>0, for Maat_cmd_select
 	struct Maat_group_t* groups;// Add regions with Maat_add_region2cmd 
 };
@@ -119,11 +119,13 @@ struct Maat_line_t
 {
 	const char* table_name;
 	const char* table_line;
-	int rule_id;
+	int rule_id;		// for MAAT_OP_DEL, only rule_id is necessary.
 	int label_id;
 	int expire_after;	//expired after $timeout$ seconds, set to 0 for never timeout.
 };
 struct Maat_cmd_t* Maat_create_cmd(const struct Maat_rule_t* rule, int group_num);
+//input: which_group 0~group_num
+//input: region can be freed after added.
 void Maat_add_region2cmd(struct Maat_cmd_t* cmd,int which_group,const struct Maat_region_t* region);
 
 void Maat_free_cmd(struct Maat_cmd_t* cmd);
diff --git a/inc/Maat_rule.h b/inc/Maat_rule.h
index 2227528..fc9d0c5 100644
--- a/inc/Maat_rule.h
+++ b/inc/Maat_rule.h
@@ -51,9 +51,9 @@ typedef	void*	Maat_feather_t;
 #define	MAX_SERVICE_DEFINE_LEN	128
 struct Maat_rule_t
 {
-	int 	config_id;
+	int		config_id;
 	int		service_id;
-	char 	do_log;
+	char	do_log;
 	char 	do_blacklist;
 	char	action;
 	char	resevered;
diff --git a/src/entry/sfh_internal.h b/src/entry/sfh_internal.h
index a259826..58fd214 100644
--- a/src/entry/sfh_internal.h
+++ b/src/entry/sfh_internal.h
@@ -29,7 +29,6 @@
 
 #define DEBUG (0)
 
-int hash_length;
 //int count = 0;
 struct roll_state_t
 {