diff --git a/qse/include/qse/cmn/chr.h b/qse/include/qse/cmn/chr.h
index b0af70d9..79a78663 100644
--- a/qse/include/qse/cmn/chr.h
+++ b/qse/include/qse/cmn/chr.h
@@ -1,5 +1,5 @@
 /*
- * $Id: chr.h 323 2010-04-05 12:50:01Z hyunghwan.chung $
+ * $Id: chr.h 356 2010-09-07 12:29:25Z hyunghwan.chung $
  *
     Copyright 2006-2009 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -24,10 +24,8 @@
 #include <qse/types.h>
 #include <qse/macros.h>
 
-/****t* Common/qse_ccls_id_t
- * NAME
- *  qse_ccls_id_t - define character class types
- * SYNOPSIS
+/**
+ * The qse_ccls_id_t type defines character class types.
  */
 enum qse_ccls_id_t
 {
@@ -44,7 +42,6 @@ enum qse_ccls_id_t
         QSE_CCLS_PUNCT
 };
 typedef enum qse_ccls_id_t qse_ccls_id_t;
-/******/
 
 #ifdef USE_STDC
 #	if defined(QSE_CHAR_IS_MCHAR)
diff --git a/qse/include/qse/cmn/dll.h b/qse/include/qse/cmn/dll.h
index c895e561..c85c9ffc 100644
--- a/qse/include/qse/cmn/dll.h
+++ b/qse/include/qse/cmn/dll.h
@@ -1,5 +1,5 @@
 /*
- * $Id: dll.h 354 2010-09-03 12:50:08Z hyunghwan.chung $
+ * $Id: dll.h 356 2010-09-07 12:29:25Z hyunghwan.chung $
  *
     Copyright 2006-2009 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -109,7 +109,7 @@
 
 #define QSE_DLL_HEAD(dll) QSE_GDL_HEAD(&(dll)->gdl)
 #define QSE_DLL_TAIL(dll) QSE_GDL_TAIL(&(dll)->gdl)
-#define QSE_DLL_SIZE(dll) ((dll)->size)
+#define QSE_DLL_SIZE(dll) ((const qse_size_t)(dll)->size)
 
 /**
  * The QSE_DLL_ADDHEAD macro add a member node @a x to the head of 
@@ -219,11 +219,10 @@ struct qse_dll_t
 #define QSE_DLL_COPIER_SIMPLE ((qse_dll_copier_t)1)
 #define QSE_DLL_COPIER_INLINE ((qse_dll_copier_t)2)
 
-#define QSE_DLL_SCALE(dll) ((dll)->scale)
+#define QSE_DLL_SCALE(dll) ((const int)(dll)->scale)
 #define QSE_DLL_DPTR(node) ((node)->dptr)
 #define QSE_DLL_DLEN(node) ((node)->dlen)
 
-
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -323,6 +322,21 @@ qse_dll_freeer_t qse_dll_getfreeer (
 	qse_dll_t* dll /**< doubly linked list */
 );
 
+/**
+ * The qse_dll_getcomper() function returns the data comparator.
+ */
+qse_dll_comper_t qse_dll_getcomper (
+	qse_dll_t* dll  /**< doubly linked list */
+);
+
+/**
+ * The qse_dll_setcomper() function changes the data comparator
+ */
+void qse_dll_setcomper (
+	qse_dll_t*       dll,    /**< doubly linked list */
+	qse_dll_comper_t comper  /**< comparator */
+);
+
 /**
  * The qse_dll_getsize() function returns the number of the data nodes held
  * in a doubly linked list.
diff --git a/qse/include/qse/cmn/htb.h b/qse/include/qse/cmn/htb.h
index 8871486b..87bb8934 100644
--- a/qse/include/qse/cmn/htb.h
+++ b/qse/include/qse/cmn/htb.h
@@ -1,5 +1,5 @@
 /*
- * $Id: htb.h 355 2010-09-07 10:57:43Z hyunghwan.chung $
+ * $Id: htb.h 356 2010-09-07 12:29:25Z hyunghwan.chung $
  *
     Copyright 2006-2009 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -158,7 +158,6 @@ struct qse_htb_t
 
 	qse_byte_t       scale[2]; /**< length scale */
 	qse_byte_t       factor;   /**< load factor in percentage */
-	qse_byte_t       filler0;
 
 	qse_size_t       size;
 	qse_size_t       capa;
@@ -173,26 +172,17 @@ struct qse_htb_t
 /**
  * The QSE_HTB_SIZE() macro returns the number of pairs in a hash table.
  */
-#define QSE_HTB_SIZE(m) ((m)->size)
+#define QSE_HTB_SIZE(m) ((const qse_size_t)(m)->size)
 
 /**
  * The QSE_HTB_CAPA() macro returns the maximum number of pairs that can be
  * stored in a hash table without further reorganization.
  */
-#define QSE_HTB_CAPA(m) ((m)->capa)
+#define QSE_HTB_CAPA(m) ((const qse_size_t)(m)->capa)
 
-#define QSE_HTB_KCOPIER(m)   ((m)->copier[QSE_HTB_KEY])
-#define QSE_HTB_VCOPIER(m)   ((m)->copier[QSE_HTB_VAL])
-#define QSE_HTB_KFREEER(m)   ((m)->freeer[QSE_HTB_KEY])
-#define QSE_HTB_VFREEER(m)   ((m)->freeer[QSE_HTB_VAL])
-#define QSE_HTB_HASHER(m)    ((m)->hasher)
-#define QSE_HTB_COMPER(m)    ((m)->comper)
-#define QSE_HTB_KEEPER(m)    ((m)->keeper)
-#define QSE_HTB_SIZER(m)     ((m)->sizer)
-
-#define QSE_HTB_FACTOR(m)    ((m)->factor)
-#define QSE_HTB_KSCALE(m)    ((m)->scale[QSE_HTB_KEY])
-#define QSE_HTB_VSCALE(m)    ((m)->scale[QSE_HTB_VAL])
+#define QSE_HTB_FACTOR(m) ((const int)(m)->factor)
+#define QSE_HTB_KSCALE(m) ((const int)(m)->scale[QSE_HTB_KEY])
+#define QSE_HTB_VSCALE(m) ((const int)(m)->scale[QSE_HTB_VAL])
 
 #define QSE_HTB_KPTR(p) ((p)->kptr)
 #define QSE_HTB_KLEN(p) ((p)->klen)
@@ -364,7 +354,7 @@ void qse_htb_setsizer (
 );
 
 /**
- * The qse_htb_search() function searches hash table to find a pair with a 
+ * The qse_htb_search() function searches a hash table to find a pair with a 
  * matching key. It returns the pointer to the pair found. If it fails
  * to find one, it returns QSE_NULL.
  * @return pointer to the pair with a maching key, 
@@ -377,7 +367,7 @@ qse_htb_pair_t* qse_htb_search (
 );
 
 /**
- * The qse_htb_upsert() function searches hash table for the pair with a 
+ * The qse_htb_upsert() function searches a hash table for the pair with a 
  * matching key. If one is found, it updates the pair. Otherwise, it inserts
  * a new pair with the key and value given. It returns the pointer to the 
  * pair updated or inserted.
diff --git a/qse/include/qse/cmn/lda.h b/qse/include/qse/cmn/lda.h
index fa72c167..32c67e3f 100644
--- a/qse/include/qse/cmn/lda.h
+++ b/qse/include/qse/cmn/lda.h
@@ -1,5 +1,5 @@
 /*
- * $Id: lda.h 341 2010-08-04 07:25:48Z hyunghwan.chung $
+ * $Id: lda.h 356 2010-09-07 12:29:25Z hyunghwan.chung $
  *
     Copyright 2006-2009 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -45,19 +45,13 @@ typedef enum   qse_lda_walk_t qse_lda_walk_t;
 
 #define QSE_LDA_NIL ((qse_size_t)-1)
 
-#define QSE_LDA_SIZE(lda)        ((lda)->size)
-#define QSE_LDA_CAPA(lda)        ((lda)->capa)
+#define QSE_LDA_SIZE(lda)        ((const qse_size_t)(lda)->size)
+#define QSE_LDA_CAPA(lda)        ((const qse_size_t)(lda)->capa)
 
 #define QSE_LDA_NODE(lda,index)  ((lda)->node[index])
 #define QSE_LDA_DPTR(lda,index)  ((lda)->node[index]->dptr)
 #define QSE_LDA_DLEN(lda,index)  ((lda)->node[index]->dlen)
 
-#define QSE_LDA_COPIER(lda)      ((lda)->copier)
-#define QSE_LDA_FREEER(lda)      ((lda)->freeer)
-#define QSE_LDA_COMPER(lda)      ((lda)->comper)
-#define QSE_LDA_KEEPER(lda)      ((lda)->keeper)
-#define QSE_LDA_SIZER(lda)       ((lda)->sizer)
-
 /**
  *  The qse_lda_copier_t type defines a callback function for node construction.
  *  A node is contructed when a user adds data to a list. The user can
diff --git a/qse/include/qse/cmn/oht.h b/qse/include/qse/cmn/oht.h
index 22272f7f..040c39c4 100644
--- a/qse/include/qse/cmn/oht.h
+++ b/qse/include/qse/cmn/oht.h
@@ -18,18 +18,47 @@
     License along with QSE. If not, see <http://www.gnu.org/licenses/>.
  */
 
+#ifndef _QSE_OHT_T_
+#define _QSE_OHT_T_
+
 /** @file
  * This file provides the open-addressed hash table for fixed-size data.
  */
-#ifndef _QSE_OHT_T_
-#define _QSE_OHT_T_
 
 #include <qse/types.h>
 #include <qse/macros.h>
 
-#define QSE_OHT_INVALID_INDEX ((qse_size_t)-1)
+/**
+ * The #QSE_OHT_NIL macro represents an invalid index.
+ */
+#define QSE_OHT_NIL ((qse_size_t)-1)
 
-enum  qse_oht_mark_t
+/**
+ * The #QSE_OHT_SIZE macro returns the number of items.
+ */
+#define QSE_OHT_SIZE(oht)  ((const qse_size_t)(oht)->size)
+
+/**
+ * The #QSE_OHT_CAPA macro returns the capacity of a table.
+ */
+#define QSE_OHT_CAPA(oht)  ((const qse_size_t)(oht)->capa.hard)
+
+/**
+ * The #QSE_OHT_LIMIT macro returns the maximum number of items.
+ * It is equal to or less than the capacity.
+ */
+#define QSE_OHT_LIMIT(oht) ((const qse_size_t)(oht)->capa.soft)
+
+/**
+ * The #QSE_OHT_SCALE macro returns the size of an item in bytes.
+ */
+#define QSE_OHT_SCALE(oht) ((const int)(oht)->scale)
+
+/**
+ * The #qse_oht_mark_t type defines enumerations values to indicate
+ * the slot status.
+ */
+enum qse_oht_mark_t
 {
 	QSE_OHT_EMPTY    = 0,
 	QSE_OHT_OCCUPIED = 1 /*,
@@ -37,6 +66,9 @@ enum  qse_oht_mark_t
 };
 typedef enum qse_oht_mark_t qse_oht_mark_t;
 
+/**
+ * The #qse_oht_walk_t type defines walking directions.
+ */
 enum qse_oht_walk_t
 {
 	QSE_OHT_WALK_STOP     = 0,
@@ -47,7 +79,15 @@ typedef enum qse_oht_walk_t qse_oht_walk_t;
 typedef struct qse_oht_t qse_oht_t;
 
 /**
- * The qse_oht_comper_t type defines a key comparator that is called when
+ * The #qse_oht_hasher_t type defines a data hasher function.
+ */
+typedef qse_size_t (*qse_oht_hasher_t) (
+	qse_oht_t*  oht,
+	const void* data
+);
+
+/**
+ * The #qse_oht_comper_t type defines a key comparator that is called when
  * the list needs to compare data.  The comparator must return 0 if the data
  * are the same and a non-zero integer otherwise.
  */
@@ -57,28 +97,30 @@ typedef int (*qse_oht_comper_t) (
 	const void* data2  /**< data pointer */
 );
 
+/**
+ * The #qse_oht_copier_t type defines a data copier function.
+ */
 typedef void (*qse_oht_copier_t) (
 	qse_oht_t*  oht,
 	void*       dst,
 	const void* src 
 );
 
-typedef qse_size_t (*qse_oht_hasher_t) (
-	qse_oht_t*  oht,
-	const void* data
-);
-
+/**
+ * The #qse_oht_t type defines an open-address hash table for fixed-size data.
+ * Unlike #qse_rbt_t or #qse_htb_t, it does not separate a key from a value.
+ */
 struct qse_oht_t
 {
 	QSE_DEFINE_COMMON_FIELDS(oht)
 
+	int scale;
 	struct
 	{
 		qse_size_t hard;
 		qse_size_t soft;
 	} capa;
 	qse_size_t size;
-	qse_size_t scale;
 
 	qse_oht_hasher_t hasher;
 	qse_oht_comper_t comper;
@@ -88,6 +130,10 @@ struct qse_oht_t
 	void*           data;
 };
 
+/**
+ * The #qse_oht_walker_t function defines a callback function 
+ * for qse_oht_walk().
+ */
 typedef qse_oht_walk_t (*qse_oht_walker_t) (
 	qse_oht_t* oht,
 	void*      data,
@@ -100,90 +146,157 @@ extern "C" {
 
 QSE_DEFINE_COMMON_FUNCTIONS (oht)
 
+/**
+ * The qse_oht_open() function creates an open-addressed hash table.
+ */
 qse_oht_t* qse_oht_open (
 	qse_mmgr_t* mmgr,
 	qse_size_t  xtnsize,
-	qse_size_t  scale,
+	int         scale,
 	qse_size_t  capa,
 	qse_size_t  limit
 );
 
+/**
+ * The qse_oht_close() function destroys an open-addressed hash table.
+ */
 void qse_oht_close (
-	qse_oht_t* oht
+	qse_oht_t* oht  /**< open-addressed hash table */
 );
 
+/**
+ * The qse_oht_open() function initializes a statically declared 
+ * open-addressed hash table.
+ */
 qse_oht_t* qse_oht_init (
 	qse_oht_t*  oht,
 	qse_mmgr_t* mmgr,
-	qse_size_t  scale,
+	int         scale,
 	qse_size_t  capa,
 	qse_size_t  limit
 );
 
+/**
+ * The qse_oht_close() function finalizes an open-addressed hash table.
+ */
 void qse_oht_fini (
-	qse_oht_t* oht
+	qse_oht_t* oht  /**< open-addressed hash table */
 );
 
+/**
+ * The qse_oht_getcomper() function returns the data hasher.
+ */
 qse_oht_hasher_t qse_oht_gethasher (
-	qse_oht_t* oht
+	qse_oht_t* oht  /**< open-addressed hash table */
 );
 
+/**
+ * The qse_oht_setcomper() function changes the data hasher
+ */
 void qse_oht_sethasher (
-	qse_oht_t*       oht,
-	qse_oht_hasher_t hahser
+	qse_oht_t*       oht,    /**< open-addressed hash table */
+	qse_oht_hasher_t hasher  /**< hasher */
 );
 
+/**
+ * The qse_oht_getcomper() function returns the data comparator.
+ */
 qse_oht_comper_t qse_oht_getcomper (
-	qse_oht_t* oht
+	qse_oht_t* oht  /**< open-addressed hash table */
 );
 
+/**
+ * The qse_oht_setcomper() function changes the data comparator
+ */
 void qse_oht_setcomper (
-	qse_oht_t*       oht,
-	qse_oht_comper_t hahser
+	qse_oht_t*       oht,    /**< open-addressed hash table */
+	qse_oht_comper_t comper  /**< comparator */
 );
 
+/**
+ * The qse_oht_getcomper() function returns the data copier.
+ */
 qse_oht_copier_t qse_oht_getcopier (
-	qse_oht_t* oht
+	qse_oht_t*       oht     /**< open-addressed hash table */
 );
 
+/**
+ * The qse_oht_setcomper() function changes the data copier.
+ */
 void qse_oht_setcopier (
-	qse_oht_t*       oht,
-	qse_oht_copier_t hahser
+	qse_oht_t*       oht,    /**< open-addressed hash table */
+	qse_oht_copier_t copier  /**< copier */
 );
 
+/**
+ * The qse_oht_search() function searches a hash table to find a 
+ * matching datum. It returns the index to the slot of an internal array
+ * where the matching datum is found. 
+ * @return slot index if a match if found,
+ *         #QSE_OHT_NIL if no match is found.
+ */
 qse_size_t qse_oht_search (
-	qse_oht_t* oht,
-	void*      data
+	qse_oht_t*       oht,    /**< open-addressed hash table */
+	void*            data    /**< data pointer */
 );
 
+/**
+ * The qse_oht_insert() function inserts a new datum. It fails if it finds
+ * an existing datum.
+ * @return slot index where the new datum is inserted on success,
+ *         #QSE_OHT_NIL on failure.
+ */
 qse_size_t qse_oht_insert (
-	qse_oht_t*  oht,
-	const void* data
+	qse_oht_t*       oht,    /**< open-addressed hash table */
+	const void*      data    /**< data pointer */
 );
 
+/**
+ * The qse_oht_upsert() function inserts a new datum if it finds no matching
+ * datum or updates an exsting datum if finds a matching datum.
+ * @return slot index where the datum is inserted or updated.
+ */
 qse_size_t qse_oht_upsert (
-	qse_oht_t*  oht,
-	const void* data
+	qse_oht_t*       oht,    /**< open-addressed hash table */
+	const void*      data    /**< data pointer */
 );
 
+/**
+ * The qse_oht_update() function updates an existing datum. It fails if it finds
+ * no existing datum.
+ * @return slot index where an existing datum is updated on success,
+ *         #QSE_OHT_NIL on failure.
+ */
 qse_size_t qse_oht_update (
-	qse_oht_t*  oht,
-	const void* data
+	qse_oht_t*       oht,    /**< open-addressed hash table */
+	const void*      data    /**< data pointer */
 );
 
+/**
+ * The qse_oht_delete() function deletes an existing datum. It fails if it finds
+ * no existing datum.
+ * @return slot index where an existing datum is deleted on success,
+ *         #QSE_OHT_NIL on failure.
+ */
 qse_size_t qse_oht_delete (
-	qse_oht_t*  oht,
-	const void* data
+	qse_oht_t*       oht,    /**< open-addressed hash table */
+	const void*      data    /**< data pointer */
 );
 
+/**
+ * The qse_oht_clear() functions deletes all data items.
+ */
 void qse_oht_clear (
-	qse_oht_t* oht
+	qse_oht_t*       oht     /**< open-addressed hash table */
 );
 
-
+/**
+ * The qse_oht_walk() function executes the callback function @a walker for
+ * each valid data item.
+ */
 void qse_oht_walk (
 	qse_oht_t*       oht,    /**< open-addressed hash table */
-	qse_oht_walker_t walker, /**< walker function */
+	qse_oht_walker_t walker, /**< callback function */
 	void*            ctx     /**< context */
 );
 
diff --git a/qse/include/qse/cmn/rbt.h b/qse/include/qse/cmn/rbt.h
index f18ff390..597b15dc 100644
--- a/qse/include/qse/cmn/rbt.h
+++ b/qse/include/qse/cmn/rbt.h
@@ -143,8 +143,6 @@ struct qse_rbt_t
 	qse_rbt_keeper_t keeper;    /**< value keeper */
 
 	qse_byte_t       scale[2];  /**< length scale */
-	qse_byte_t       factor;    /**< load factor */
-	qse_byte_t       filler0;
 
 	qse_rbt_pair_t   nil;       /**< internal nil node */
 
@@ -167,18 +165,9 @@ struct qse_rbt_t
 /**
  * The QSE_RBT_SIZE() macro returns the number of pairs in red-black tree.
  */
-#define QSE_RBT_SIZE(m) ((m)->size)
-
-#define QSE_RBT_KCOPIER(m)   ((m)->copier[QSE_RBT_KEY])
-#define QSE_RBT_VCOPIER(m)   ((m)->copier[QSE_RBT_VAL])
-#define QSE_RBT_KFREEER(m)   ((m)->freeer[QSE_RBT_KEY])
-#define QSE_RBT_VFREEER(m)   ((m)->freeer[QSE_RBT_VAL])
-#define QSE_RBT_COMPER(m)    ((m)->comper)
-#define QSE_RBT_KEEPER(m)    ((m)->keeper)
-
-#define QSE_RBT_FACTOR(m)    ((m)->factor)
-#define QSE_RBT_KSCALE(m)    ((m)->scale[QSE_RBT_KEY])
-#define QSE_RBT_VSCALE(m)    ((m)->scale[QSE_RBT_VAL])
+#define QSE_RBT_SIZE(m)   ((const qse_size_t)(m)->size)
+#define QSE_RBT_KSCALE(m) ((const int)(m)->scale[QSE_RBT_KEY])
+#define QSE_RBT_VSCALE(m) ((const int)(m)->scale[QSE_RBT_VAL])
 
 #define QSE_RBT_KPTR(p) ((p)->kptr)
 #define QSE_RBT_KLEN(p) ((p)->klen)
diff --git a/qse/include/qse/cmn/sll.h b/qse/include/qse/cmn/sll.h
index f262ef15..632890d4 100644
--- a/qse/include/qse/cmn/sll.h
+++ b/qse/include/qse/cmn/sll.h
@@ -1,5 +1,5 @@
 /*
- * $Id: sll.h 355 2010-09-07 10:57:43Z hyunghwan.chung $
+ * $Id: sll.h 356 2010-09-07 12:29:25Z hyunghwan.chung $
  *
     Copyright 2006-2009 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -131,14 +131,10 @@ struct qse_sll_node_t
 #define QSE_SLL_COPIER_SIMPLE ((qse_sll_copier_t)1)
 #define QSE_SLL_COPIER_INLINE ((qse_sll_copier_t)2)
 
-#define QSE_SLL_COPIER(sll) ((sll)->copier)
-#define QSE_SLL_FREEER(sll) ((sll)->freeer)
-#define QSE_SLL_COMPER(sll) ((sll)->comper)
-
 #define QSE_SLL_HEAD(sll)   ((sll)->head)
 #define QSE_SLL_TAIL(sll)   ((sll)->tail)
-#define QSE_SLL_SIZE(sll)   ((sll)->size)
-#define QSE_SLL_SCALE(sll)  ((sll)->scale)
+#define QSE_SLL_SIZE(sll)   ((const qse_size_t)(sll)->size)
+#define QSE_SLL_SCALE(sll)  ((const int)(sll)->scale)
 
 /**
  * The QSE_SLL_DPTR macro gets the data pointer in a node.
@@ -278,7 +274,7 @@ qse_sll_comper_t qse_sll_getcomper (
  * The qse_sll_setcomper() function changes  the data comparator
  */
 void qse_sll_setcomper (
-	qse_sll_t*       sll     /**< singly linked list */,
+	qse_sll_t*       sll,    /**< singly linked list */
 	qse_sll_comper_t comper  /**< comparator */
 );
 
diff --git a/qse/include/qse/cmn/str.h b/qse/include/qse/cmn/str.h
index 2cf54b9b..38dfb397 100644
--- a/qse/include/qse/cmn/str.h
+++ b/qse/include/qse/cmn/str.h
@@ -1,5 +1,5 @@
 /*
- * $Id: str.h 354 2010-09-03 12:50:08Z hyunghwan.chung $
+ * $Id: str.h 356 2010-09-07 12:29:25Z hyunghwan.chung $
  *
     Copyright 2006-2009 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -32,11 +32,10 @@
  *
  */
 
-#define QSE_STR_LEN(s)       ((s)->len)      /**< string length */
-#define QSE_STR_PTR(s)       ((s)->ptr)      /**< string/buffer pointer */
-#define QSE_STR_CAPA(s)      ((s)->capa)     /**< buffer capacity */
+#define QSE_STR_LEN(s)       ((const qse_size_t)(s)->len) /**< string length */
+#define QSE_STR_PTR(s)       ((qse_char_t* const)(s)->ptr) /**< string/buffer pointer */
+#define QSE_STR_CAPA(s)      ((qse_size_t)(s)->capa) /**< buffer capacity */
 #define QSE_STR_CHAR(s,idx)  ((s)->ptr[idx]) /**< character at given position */
-#define QSE_STR_SIZER(s)     ((s)->sizer)    /**< buffer resizer function */
 
 typedef struct qse_str_t qse_str_t;
 
diff --git a/qse/include/qse/cmn/time.h b/qse/include/qse/cmn/time.h
index 4d31d5c3..310f4088 100644
--- a/qse/include/qse/cmn/time.h
+++ b/qse/include/qse/cmn/time.h
@@ -1,5 +1,5 @@
 /*
- * $Id: time.h 287 2009-09-15 10:01:02Z hyunghwan.chung $
+ * $Id: time.h 356 2010-09-07 12:29:25Z hyunghwan.chung $
  *
     Copyright 2006-2009 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -21,6 +21,10 @@
 #ifndef _QSE_CMN_TIME_H_
 #define _QSE_CMN_TIME_H_
 
+/** @file
+ * This file provides time manipulation functions.
+ */
+
 #include <qse/types.h>
 #include <qse/macros.h>
 
@@ -78,20 +82,15 @@ struct qse_btime_t
 extern "C" {
 #endif
 
-/****f* Common/qse_gettime
- * NAME
- *  qse_gettime - get the current time
- * SYNPOSIS
+/**
+ * The qse_gettime() function gets the current time.
  */
 int qse_gettime (
 	qse_ntime_t* nt
 );
-/******/
 
-/****f* Common/qse_settime
- * NAME
- *  qse_settime - set the current time
- * SYNOPSIS
+/**
+ * The qse_settime() function sets the current time.
  */
 int qse_settime (
 	qse_ntime_t nt
@@ -114,7 +113,6 @@ int qse_localtime (
 	qse_ntime_t  nt, 
 	qse_btime_t* bt
 ); 
-/******/
 
 /**
  * The qse_timegm() converts broken-down time to numeric time. It is the 
@@ -125,7 +123,6 @@ int qse_timegm (
 	const qse_btime_t* bt,
 	qse_ntime_t*       nt
 );
-/******/
 
 /**
  * The qse_timelocal() converts broken-down time to numeric time. It is the
@@ -135,13 +132,9 @@ int qse_timelcoal (
 	const qse_btime_t* bt,
 	qse_ntime_t*       nt
 );
-/******/
 
-/****f* Common/qse_strftime
- * NAME
- *  qse_strftime - format time
- *
- * SYNOPSIS
+/**
+ * The qse_strftime() functions formats time.
  */
 qse_size_t qse_strftime (
         qse_char_t*       buf, 
@@ -149,7 +142,6 @@ qse_size_t qse_strftime (
 	const qse_char_t* fmt,
 	qse_btime_t*      bt
 );
-/******/
 
 #ifdef __cplusplus
 }
diff --git a/qse/include/qse/cmn/tio.h b/qse/include/qse/cmn/tio.h
index 40471a23..6077a3f9 100644
--- a/qse/include/qse/cmn/tio.h
+++ b/qse/include/qse/cmn/tio.h
@@ -1,5 +1,5 @@
 /*
- * $Id: tio.h 291 2009-09-21 13:28:18Z hyunghwan.chung $
+ * $Id: tio.h 356 2010-09-07 12:29:25Z hyunghwan.chung $
  *
     Copyright 2006-2009 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -21,11 +21,15 @@
 #ifndef _QSE_CMN_TIO_H_
 #define _QSE_CMN_TIO_H_
 
+/** @file
+ * This file provides an interface to a text stream processor.
+ */
+
 #include <qse/types.h>
 #include <qse/macros.h>
 #include <qse/cmn/str.h>
 
-enum qse_tio_err_t
+enum qse_tio_errnum_t
 {
 	QSE_TIO_ENOERR = 0,
 	QSE_TIO_ENOMEM, /* out of memory */
@@ -43,7 +47,7 @@ enum qse_tio_err_t
 	QSE_TIO_EOUTCL  /* output function failed to close */
 };
 
-typedef enum qse_tio_err_t qse_tio_err_t;
+typedef enum qse_tio_errnum_t qse_tio_errnum_t;
 
 enum
 {
@@ -62,7 +66,7 @@ enum
 	QSE_TIO_IO_DATA
 };
 
-#define QSE_TIO_ERRNUM(tio) ((tio)->errnum)
+#define QSE_TIO_ERRNUM(tio) ((const qse_tio_errnum_t)(tio)->errnum)
 
 typedef struct qse_tio_t qse_tio_t;
 
@@ -84,7 +88,7 @@ typedef qse_ssize_t (*qse_tio_io_t) (
 struct qse_tio_t
 {
 	QSE_DEFINE_COMMON_FIELDS (tio)
-	qse_tio_err_t errnum;
+	qse_tio_errnum_t errnum;
 
 	/* io functions */
 	qse_tio_io_t input_func;
@@ -123,150 +127,107 @@ int qse_tio_close (
 	qse_tio_t* tio
 );
 
-/****f* Common/qse_tio_init
- * NAME
- *  qse_tio_init - initialize an text IO processor
- * SYNOPSIS
+/**
+ * The qse_tio_init() function  initialize a statically declared 
+ * text stream processor.
  */
 qse_tio_t* qse_tio_init (
 	qse_tio_t*  tip,
 	qse_mmgr_t* mmgr
 );
-/******/
 
-/****f* Common/qse_tio_fini
- * NAME
- *  qse_tio_fini - finalize an text IO processor
- * SYNOPSIS
+/**
+ * The qse_tio_fini() function finalizes a text stream processor
  */
 int qse_tio_fini (
 	qse_tio_t* tio
 );
-/******/
 
-/****f* Common/qse_tio_geterrnum
- * NAME
- *  qse_tio_geterrnum - get an error code
- *
- * SYNOPSIS
+/**
+ * The qse_tio_geterrnum() function return an error code.
  */
-qse_tio_err_t qse_tio_geterrnum (
+qse_tio_errnum_t qse_tio_geterrnum (
 	qse_tio_t* tio
 );
-/******/
 
-/****f* Common/qse_tio_geterrmsg
- * NAME
- *  qse_tio_geterrmsg - translate an error code to a string
- * RETURN
- *   A pointer to a constant string describing the last error occurred.
+/**
+ * The qse_tio_geterrmsg() function translates an error code to a string.
+ * @return pointer to a constant string describing the last error occurred.
  */
 const qse_char_t* qse_tio_geterrmsg (
 	qse_tio_t* tio
 );
-/******/
 
-/****f* Common/qse_tio_attachin
- * NAME
- *  qse_tio_attachin - attaches an input handler 
- * RETURN
- *   0 on success, -1 on failure
- * SYNOPSIS
+/**
+ * The qse_tio_attachin() function attachs an input handler .
+ * @return 0 on success, -1 on failure
  */
 int qse_tio_attachin (
 	qse_tio_t*   tio,
 	qse_tio_io_t input,
 	void*        arg
 );
-/******/
 
-/****f* Common/qse_tio_detachin
- * NAME
- *  qse_tio_detachin - detach an input handler 
- * RETURN
- *   0 on success, -1 on failure
- * SYNOPSIS
+/**
+ * The qse_tio_detachin() function detaches an input handler .
+ * @return 0 on success, -1 on failure
  */
 int qse_tio_detachin (
 	qse_tio_t* tio
 );
-/******/
 
-/****f* Common/qse_tio_attachout
- * NAME
- *  qse_tio_attachout - attaches an output handler 
- * RETURN
- *   0 on success, -1 on failure
- * SYNOPSIS
+/**
+ * The qse_tio_attachout() function attaches an output handler.
+ * @return 0 on success, -1 on failure
  */
 int qse_tio_attachout (
 	qse_tio_t* tio,
 	qse_tio_io_t output,
 	void* arg
 );
-/******/
 
-/****f* Common/qse_tio_detachout
- * NAME
- *  qse_tio_detachout - detaches an output handler 
- * RETURN
- *   0 on success, -1 on failure
- * SYNOPSIS
+/**
+ * The qse_tio_detachout() function detaches an output handler .
+ * @return 0 on success, -1 on failure
  */
 int qse_tio_detachout (
 	qse_tio_t* tio
 );
-/******/
 
-/****f* Common/qse_tio_flush
- * NAME
- *  qse_tio_flush - flush the output buffer
- * RETURNS
- *  The qse_tio_flush() function return the number of bytes written on 
- *  success, -1 on failure.
- * SYNOPSIS
+/**
+ * The qse_tio_flush() function flushes the output buffer. It returns the 
+ * number of bytes written on success, -1 on failure.
  */
 qse_ssize_t qse_tio_flush (
 	qse_tio_t* tio
 );
-/******/
 
-/****f* Common/qse_tio_purge
- * NAME 
- *  qse_tio_purge - empty input and output buffers
- * SYNOPSIS
+/**
+ * The qse_tio_purge() function empties input and output buffers.
  */
 void qse_tio_purge (
 	qse_tio_t* tio
 );
-/******/
 
-/****f* Common/qse_tio_read
- * NAME
- *  qse_tio_read - read text
- * SYNOPSIS
+/**
+ * The qse_tio_read() functio reads text.
  */
 qse_ssize_t qse_tio_read (
 	qse_tio_t*  tio, 
 	qse_char_t* buf, 
 	qse_size_t  size
 );
-/******/
 
-/****f* Common/qse_tio_write
- * NAME
- *  qse_tio_write - write text
- * DESCRIPTION
- *  If the size paramenter is (qse_size_t)-1, the function treats the data 
- *  parameter as a pointer to a null-terminated string.
- * SYNOPSIS
+/**
+ * The qse_tio_write() function writes text.
+ * If the size paramenter is (qse_size_t)-1, the function treats the data 
+ * parameter as a pointer to a null-terminated string.
  */
 qse_ssize_t qse_tio_write (
 	qse_tio_t*        tio,
 	const qse_char_t* data,
 	qse_size_t        size
 );
-/******/
 
 #ifdef __cplusplus
 }
diff --git a/qse/lib/awk/rio.c b/qse/lib/awk/rio.c
index 542d3052..22a39fcb 100644
--- a/qse/lib/awk/rio.c
+++ b/qse/lib/awk/rio.c
@@ -1,5 +1,5 @@
 /*
- * $Id: rio.c 312 2009-12-10 13:03:54Z hyunghwan.chung $
+ * $Id: rio.c 356 2010-09-07 12:29:25Z hyunghwan.chung $
  *
     Copyright 2006-2009 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -299,7 +299,8 @@ int qse_awk_rtx_readio (
 							QSE_STR_PTR(buf) + QSE_STR_LEN(buf) ==
 							match.ptr + match.len);
 
-						QSE_STR_LEN(buf) -= match.len;
+						/*QSE_STR_LEN(buf) -= match.len;*/
+						buf->len -= match.len;
 						break;
 					}
 				}
@@ -322,7 +323,8 @@ int qse_awk_rtx_readio (
 				if (pc == QSE_T('\r') && 
 				    QSE_STR_LEN(buf) > 0) 
 				{
-					QSE_STR_LEN(buf) -= 1;
+					/*QSE_STR_LEN(buf) -= 1;*/
+					buf->len -= 1;
 				}
 				break;
 			}
@@ -335,7 +337,8 @@ int qse_awk_rtx_readio (
 				if (pc == QSE_T('\r') && 
 				    QSE_STR_LEN(buf) > 0) 
 				{
-					QSE_STR_LEN(buf) -= 1;
+					/*QSE_STR_LEN(buf) -= 1;*/
+					buf->len -= 1;
 				}
 			}
 
@@ -353,7 +356,8 @@ int qse_awk_rtx_readio (
 				/* when a blank line is encountered,
 				 * it needs to snip off the line 
 				 * terminator of the previous line */
-				QSE_STR_LEN(buf) -= 1;
+				/*QSE_STR_LEN(buf) -= 1;*/
+				buf->len -= 1;
 				break;
 			}
 		}
@@ -394,7 +398,8 @@ int qse_awk_rtx_readio (
 					QSE_STR_PTR(buf) + QSE_STR_LEN(buf) ==
 					match.ptr + match.len);
 
-				QSE_STR_LEN(buf) -= match.len;
+				/*QSE_STR_LEN(buf) -= match.len;*/
+				buf->len -= match.len;
 				p->in.pos--; /* unread the character in c */
 				break;
 			}
diff --git a/qse/lib/cmn/oht.c b/qse/lib/cmn/oht.c
index 932db5d7..6aed9942 100644
--- a/qse/lib/cmn/oht.c
+++ b/qse/lib/cmn/oht.c
@@ -44,7 +44,7 @@ static QSE_INLINE_ALWAYS void default_copier (
 
 qse_oht_t* qse_oht_open (
 	qse_mmgr_t* mmgr, qse_size_t xtnsize,
-	qse_size_t scale, qse_size_t capa, qse_size_t limit) 
+	int scale, qse_size_t capa, qse_size_t limit) 
 {
 	qse_oht_t* oht;
 
@@ -78,12 +78,12 @@ void qse_oht_close (qse_oht_t* oht)
 
 qse_oht_t* qse_oht_init (
 	qse_oht_t* oht, qse_mmgr_t* mmgr,
-	qse_size_t scale, qse_size_t capa, qse_size_t limit) 
+	int scale, qse_size_t capa, qse_size_t limit) 
 {
 	qse_size_t i;
 
 	if (scale <= 0) scale = 1;
-	if (capa >= QSE_OHT_INVALID_INDEX - 1) capa = QSE_OHT_INVALID_INDEX - 1;
+	if (capa >= QSE_OHT_NIL - 1) capa = QSE_OHT_NIL - 1;
 	if (limit > capa || limit <= 0) limit = capa;
 
 	QSE_MEMSET (oht, 0, QSE_SIZEOF(*oht));
@@ -165,13 +165,13 @@ static QSE_INLINE qse_size_t search (
 		}
 	}
 
-	return QSE_OHT_INVALID_INDEX;
+	return QSE_OHT_NIL;
 }
 
 qse_size_t qse_oht_search (qse_oht_t* oht, void* data)
 {
 	qse_size_t i = search (oht, data, HASH_DATA(oht,data));
-	if (i != QSE_OHT_INVALID_INDEX && data) 
+	if (i != QSE_OHT_NIL && data) 
 		COPY_DATA (oht, data, DATA_PTR(oht,i));
 	return i;
 }
@@ -179,7 +179,7 @@ qse_size_t qse_oht_search (qse_oht_t* oht, void* data)
 qse_size_t qse_oht_update (qse_oht_t* oht, const void* data)
 {
 	qse_size_t i = search (oht, data, HASH_DATA(oht,data));
-	if (i != QSE_OHT_INVALID_INDEX) 
+	if (i != QSE_OHT_NIL) 
 		COPY_DATA (oht, DATA_PTR(oht,i), data);
 	return i;
 }
@@ -190,14 +190,14 @@ qse_size_t qse_oht_upsert (qse_oht_t* oht, const void* data)
 
 	/* find the existing item */
 	i = search (oht, data, hash);
-	if (i != QSE_OHT_INVALID_INDEX)
+	if (i != QSE_OHT_NIL)
 	{
 		COPY_DATA (oht, DATA_PTR(oht,i), data);
 		return i;
 	}
 
 	/* check if there is a free slot to insert data into */
-	if (oht->size >= oht->capa.soft) return QSE_OHT_INVALID_INDEX;
+	if (oht->size >= oht->capa.soft) return QSE_OHT_NIL;
 
 	/* get the unoccupied slot and insert the data into it.
 	 * iterate at most 'the number of items (oht->size)' times + 1. */
@@ -213,7 +213,7 @@ qse_size_t qse_oht_upsert (qse_oht_t* oht, const void* data)
 		}
 	}
 
-	return QSE_OHT_INVALID_INDEX;
+	return QSE_OHT_NIL;
 }
 
 qse_size_t qse_oht_insert (qse_oht_t* oht, const void* data)
@@ -221,13 +221,13 @@ qse_size_t qse_oht_insert (qse_oht_t* oht, const void* data)
 	qse_size_t i, hash;
 
 	/* check if there is a free slot to insert data into */
-	if (oht->size >= oht->capa.soft) return QSE_OHT_INVALID_INDEX;
+	if (oht->size >= oht->capa.soft) return QSE_OHT_NIL;
 
 	hash = HASH_DATA (oht, data);
 
 	/* check if the item already exits */
 	i = search (oht, data, hash);
-	if (i != QSE_OHT_INVALID_INDEX) return QSE_OHT_INVALID_INDEX;
+	if (i != QSE_OHT_NIL) return QSE_OHT_NIL;
 
 	/* get the unoccupied slot and insert the data into it.
 	 * iterate at most 'the number of items (oht->size)' times + 1. */
@@ -243,7 +243,7 @@ qse_size_t qse_oht_insert (qse_oht_t* oht, const void* data)
 		}
 	}
 
-	return QSE_OHT_INVALID_INDEX;
+	return QSE_OHT_NIL;
 }
 
 qse_size_t qse_oht_delete (qse_oht_t* oht, const void* data)
@@ -251,10 +251,10 @@ qse_size_t qse_oht_delete (qse_oht_t* oht, const void* data)
 #if 0
 	qse_size_t index;
 
-	if (oht->size <= 0) return QSE_OHT_INVALID_INDEX; 
+	if (oht->size <= 0) return QSE_OHT_NIL; 
 
 	index = search (oht, data, HASH_DATA(oht,data));
-	if (index != QSE_OHT_INVALID_INDEX)
+	if (index != QSE_OHT_NIL)
 	{
 		oht->mark[index] = QSE_OHT_DELETED;
 		oht->size--;
@@ -266,11 +266,11 @@ qse_size_t qse_oht_delete (qse_oht_t* oht, const void* data)
 	qse_size_t index, i, x, y, z;
 
 	/* check if the oht is empty. if so, do nothing */
-	if (oht->size <= 0) return QSE_OHT_INVALID_INDEX; 
+	if (oht->size <= 0) return QSE_OHT_NIL; 
 
 	/* check if the item exists. otherwise, do nothing. */
 	index = search (oht, data, HASH_DATA(oht,data));
-	if (index == QSE_OHT_INVALID_INDEX) return QSE_OHT_INVALID_INDEX;
+	if (index == QSE_OHT_NIL) return QSE_OHT_NIL;
 
 	/* compact the cluster */
 	for (i = 0, x = index, y = index; i < oht->size; i++)
diff --git a/qse/lib/cmn/tio.c b/qse/lib/cmn/tio.c
index a4b4b5ce..341e4f6d 100644
--- a/qse/lib/cmn/tio.c
+++ b/qse/lib/cmn/tio.c
@@ -1,5 +1,5 @@
 /*
- * $Id: tio.c 348 2010-08-26 06:26:28Z hyunghwan.chung $
+ * $Id: tio.c 356 2010-09-07 12:29:25Z hyunghwan.chung $
  *
     Copyright 2006-2009 Chung, Hyung-Hwan.
     This file is part of QSE.
@@ -89,7 +89,7 @@ int qse_tio_fini (qse_tio_t* tio)
 	return 0;
 }
 
-qse_tio_err_t qse_tio_geterrnum (qse_tio_t* tio)
+qse_tio_errnum_t qse_tio_geterrnum (qse_tio_t* tio)
 {
 	return tio->errnum;
 }
diff --git a/qse/samples/cmn/oht.c b/qse/samples/cmn/oht.c
index c5d6ebd9..216e22d0 100644
--- a/qse/samples/cmn/oht.c
+++ b/qse/samples/cmn/oht.c
@@ -31,13 +31,13 @@ static qse_oht_walk_t walk2 (qse_oht_t* oht, void* data, void* ctx)
  	return QSE_OHT_WALK_FORWARD;
 }
 
-static qse_size_t hash (qse_oht_t* oht, void* data)
+static qse_size_t hash (qse_oht_t* oht, const void* data)
 {
 	item_t* item = (item_t*)data;
-	return item->a;	
+	return item->a	+ 123445;
 }
 
-static int comp (qse_oht_t* oht, void* data1, void* data2)
+static int comp (qse_oht_t* oht, const void* data1, const void* data2)
 {
 	return ((item_t*)data1)->a != ((item_t*)data2)->a;	
 }
@@ -73,6 +73,7 @@ static int test1 ()
 			x, (unsigned long)qse_oht_search (oht, &x));
 
 
+	qse_printf (QSE_T("total %lu items\n"), (unsigned long)QSE_OHT_SIZE(oht));
 	qse_oht_walk (oht, walk1, QSE_NULL);
 	qse_oht_close (oht);
 	return 0;
@@ -83,7 +84,7 @@ static int test2 ()
 	item_t x;
 	qse_oht_t* oht;
 
-	oht = qse_oht_open (QSE_NULL, 0, QSE_SIZEOF(x), 10, 5);
+	oht = qse_oht_open (QSE_NULL, 0, QSE_SIZEOF(x), 10, 10);
 	if (oht == QSE_NULL)
 	{
 		qse_printf (QSE_T("failed to open a table\n"));
@@ -114,6 +115,7 @@ static int test2 ()
 			x.a, (unsigned long)qse_oht_search (oht, &x));
 
 
+	qse_printf (QSE_T("total %lu items\n"), (unsigned long)QSE_OHT_SIZE(oht));
 	qse_oht_walk (oht, walk2, QSE_NULL);
 	qse_oht_close (oht);
 	return 0;