diff --git a/qse/include/qse/utl/sed.h b/qse/include/qse/utl/sed.h
index d966d9b9..8e1e37cc 100644
--- a/qse/include/qse/utl/sed.h
+++ b/qse/include/qse/utl/sed.h
@@ -61,6 +61,23 @@ enum qse_sed_option_t
 	QSE_SED_ENSURENL = (1 << 2)   /* ensure NL at the text end */
 };
 
+enum qse_sed_io_cmd_t
+{
+	QSE_SED_IO_OPEN  = 0,
+	QSE_SED_IO_CLOSE = 1,
+	QSE_SED_IO_READ  = 2,
+	QSE_SED_IO_WRITE = 3
+};
+
+typedef enum qse_sed_io_cmd_t qse_sed_io_cmd_t;
+
+typedef qse_ssize_t (*qse_sed_iof_t) (
+        qse_sed_t*       sed,
+        qse_sed_io_cmd_t cmd,
+        qse_char_t*      data,
+        qse_size_t       count
+);
+
 typedef struct qse_sed_t qse_sed_t;
 typedef struct qse_sed_cmd_t qse_sed_cmd_t; /* command */
 typedef enum qse_sed_errnum_t qse_sed_errnum_t;
@@ -186,7 +203,8 @@ int qse_sed_compile (
 );
 
 int qse_sed_execute (
-	qse_sed_t* sed
+	qse_sed_t*     sed,
+	qse_sed_iof_t* iof
 );
 
 #ifdef __cplusplus
diff --git a/qse/lib/cmn/map.c b/qse/lib/cmn/map.c
index 1b220da9..8273527b 100644
--- a/qse/lib/cmn/map.c
+++ b/qse/lib/cmn/map.c
@@ -1,5 +1,5 @@
 /*
- * $Id: map.c 76 2009-02-22 14:18:06Z hyunghwan.chung $
+ * $Id: map.c 120 2009-04-10 05:00:00Z hyunghwan.chung $
  *
    Copyright 2006-2009 Chung, Hyung-Hwan.
 
@@ -411,9 +411,8 @@ pair_t* qse_map_search (map_t* map, const void* kptr, size_t klen)
 	return QSE_NULL;
 }
 
-static int map_put (
-	map_t* map, void* kptr, size_t klen, 
-	void* vptr, size_t vlen, pair_t** px)
+pair_t* qse_map_upsert (
+	map_t* map, void* kptr, size_t klen, void* vptr, size_t vlen)
 {
 	pair_t* pair, * p, * prev, * next;
 	size_t hc;
@@ -429,7 +428,7 @@ static int map_put (
 		if (map->comper (map, KPTR(pair), KLEN(pair), kptr, klen) == 0) 
 		{
 			p = change_pair_val (map, pair, vptr, vlen);
-			if (p == QSE_NULL) return -1; /* change error */
+			if (p == QSE_NULL) return QSE_NULL; /* change error */
 			if (p != pair) 
 			{
 				/* the pair has been reallocated. relink it */
@@ -438,8 +437,7 @@ static int map_put (
 				NEXT(p) = next;
 			}
 
-			if (px != QSE_NULL) *px = p;
-			return 0; /* value changed for the existing key */
+			return p; /* value changed for the existing key */
 		}
 
 		prev = pair;
@@ -457,26 +455,13 @@ static int map_put (
 	QSE_ASSERT (pair == QSE_NULL);
 
 	pair = alloc_pair (map, kptr, klen, vptr, vlen);
-	if (pair == QSE_NULL) return -1; /* error */
+	if (pair == QSE_NULL) return QSE_NULL; /* error */
 
 	NEXT(pair) = map->bucket[hc];
 	map->bucket[hc] = pair;
 	map->size++;
 
-	if (px != QSE_NULL) *px = pair;
-	return 1; /* new key added */
-}
-
-pair_t* qse_map_upsert (
-	map_t* map, void* kptr, size_t klen, void* vptr, size_t vlen)
-{
-	/* update if the key exists, otherwise insert a new pair */
-	int n;
-	pair_t* px;
-
-	n = map_put (map, kptr, klen, vptr, vlen, &px);
-	if (n < 0) return QSE_NULL;
-	return px;
+	return pair; /* new key added */
 }
 
 pair_t* qse_map_insert (map_t* map, void* kptr, size_t klen, void* vptr, size_t vlen)
diff --git a/qse/lib/utl/sed.c b/qse/lib/utl/sed.c
index cf7a70df..d31358fb 100644
--- a/qse/lib/utl/sed.c
+++ b/qse/lib/utl/sed.c
@@ -23,11 +23,6 @@
 /* TODO: delete stdio.h */
 #include <qse/utl/stdio.h>
 
-/* POSIX http://www.opengroup.org/onlinepubs/009695399/utilities/sed.html 
- * ALSO READ
-    http://www.freebsd.org/cgi/cvsweb.cgi/src/usr.bin/sed/POSIX?rev=1.4.6.1;content-type=text%2Fplain 
- */
-
 QSE_IMPLEMENT_COMMON_FUNCTIONS (sed)
 
 qse_sed_t* qse_sed_open (qse_mmgr_t* mmgr, qse_size_t xtn)
@@ -1197,15 +1192,47 @@ int qse_sed_compile (qse_sed_t* sed, const qse_char_t* sptr, qse_size_t slen)
 	return compile_source (sed, sptr, slen);	
 }
 
-int qse_sed_execute (qse_sed_t* sed)
+static int read_line (qse_sed_t* sed, qse_sed_iof_t* iof)
+{
+}
+
+int qse_sed_execute (qse_sed_t* sed, qse_sed_iof_t* iof)
 {
 	qse_sed_cmd_t* c = sed->cmd.buf;
-	
+	qse_ssize_t n;
+	int ret = 0;
+
+	n = iof (sed, QSE_SED_IO_OPEN, QSE_NULL, 0);
+	if (n == 0) goto done; /* EOF reached upon opening a stream */
+	if (n == -1)
+	{
+		ret = -1;
+		sed->errnum = QSE_SED_EIO;
+		goto done;
+	}
+
+	while (1)
+	{
+	}
+
+done:
+	iof (sed, QSE_SED_IO_CLOSE, QSE_NULL< 0);
+	return ret;
+
+#if 0
 	while (c < sed->cmd.cur)
 	{
 		qse_printf (QSE_T(">>> %c\n"), c->type);
+
+		switch (c->type)
+		{
+			case QSE_CMD_
+		}
+
 		c++;
 	}
 
 	return 0;
+#endif
+
 }