diff --git a/qse/cmd/http/httpd.c b/qse/cmd/http/httpd.c
index 25ba43e0..f6682a9f 100644
--- a/qse/cmd/http/httpd.c
+++ b/qse/cmd/http/httpd.c
@@ -1237,7 +1237,7 @@ static int load_server_config (qse_httpd_t* httpd, qse_httpd_server_t* server, q
 		qse_xli_pair_t* host;
 		qse_char_t buf[32];
 
-		qse_sprintf (buf, QSE_COUNTOF(buf), QSE_T("host[%d]"), i);
+		qse_strxfmt (buf, QSE_COUNTOF(buf), QSE_T("host[%d]"), i);
 		host = qse_xli_findpair (httpd_xtn->xli, list, buf);
 		if (!host) break;
 
@@ -1254,7 +1254,7 @@ static int load_server_config (qse_httpd_t* httpd, qse_httpd_server_t* server, q
 
 				j--;
 
-				qse_sprintf (buf, QSE_COUNTOF(buf), QSE_T("location[%d]"), j);
+				qse_strxfmt (buf, QSE_COUNTOF(buf), QSE_T("location[%d]"), j);
 				loc = qse_xli_findpair (httpd_xtn->xli, (qse_xli_list_t*)host->val, buf);
 				if (!loc) break;
 
@@ -1605,7 +1605,7 @@ static int load_config (qse_httpd_t* httpd)
 	for (i = 0; ; i++)
 	{
 		qse_char_t buf[32];
-		qse_sprintf (buf, QSE_COUNTOF(buf), QSE_T("server[%d]"), i);
+		qse_strxfmt (buf, QSE_COUNTOF(buf), QSE_T("server[%d]"), i);
 		pair = qse_xli_findpair (httpd_xtn->xli, QSE_NULL, buf);
 		if (pair == QSE_NULL) break;
 
@@ -1669,7 +1669,7 @@ static void reconf_server (qse_httpd_t* httpd, qse_httpd_server_t* server)
 	if (httpd_xtn->xli)
 	{
 		qse_char_t buf[32];
-		qse_sprintf (buf, QSE_COUNTOF(buf), QSE_T("server[%d]"), server_xtn->num);
+		qse_strxfmt (buf, QSE_COUNTOF(buf), QSE_T("server[%d]"), server_xtn->num);
 		pair = qse_xli_findpair (httpd_xtn->xli, QSE_NULL, buf);
 
 		if (pair && pair->val->type == QSE_XLI_LIST) 
diff --git a/qse/include/qse/cmn/sio.h b/qse/include/qse/cmn/sio.h
index 394f32a5..1ae6c2ef 100644
--- a/qse/include/qse/cmn/sio.h
+++ b/qse/include/qse/cmn/sio.h
@@ -319,12 +319,6 @@ QSE_EXPORT qse_ssize_t qse_sio_putwcsf (
 	...
 );
 
-QSE_EXPORT qse_ssize_t qse_sio_putstrf (
-	qse_sio_t*        sio,
-	const qse_char_t* fmt,
-	...
-);
-
 QSE_EXPORT qse_ssize_t qse_sio_putmbsvf (
 	qse_sio_t*         sio,
 	const qse_mchar_t* fmt,
@@ -337,20 +331,18 @@ QSE_EXPORT qse_ssize_t qse_sio_putwcsvf (
 	va_list            ap
 );
 
-QSE_EXPORT qse_ssize_t qse_sio_putstrvf (
-	qse_sio_t*        sio,
-	const qse_char_t* fmt,
-	va_list           ap
-);
-
 #if defined(QSE_CHAR_IS_MCHAR)
 #	define qse_sio_putc(sio,c) qse_sio_putmb(sio,c)
 #	define qse_sio_putstr(sio,str) qse_sio_putmbs(sio,str)
 #	define qse_sio_putstrn(sio,str,size) qse_sio_putmbsn(sio,str,size)
+#	define qse_sio_putstrf qse_sio_putmbsf
+#	define qse_sio_putstrvf(sio,fmt,ap) qse_sio_putmbsvf(sio,fmt,ap)
 #else
 #	define qse_sio_putc(sio,c) qse_sio_putwc(sio,c)
 #	define qse_sio_putstr(sio,str) qse_sio_putwcs(sio,str)
 #	define qse_sio_putstrn(sio,str,size) qse_sio_putwcsn(sio,str,size)
+#	define qse_sio_putstrf qse_sio_putwcsf
+#	define qse_sio_putstrvf(sio,fmt,ap) qse_sio_putwcsvf(sio,fmt,ap)
 #endif
 
 /**
@@ -393,11 +385,6 @@ QSE_EXPORT qse_ssize_t qse_putwcsf (
 	...
 );
 
-QSE_EXPORT qse_ssize_t qse_putstrf (
-	const qse_char_t* fmt,
-	...
-);
-
 QSE_EXPORT qse_ssize_t qse_putmbsvf (
 	const qse_mchar_t* fmt,
 	va_list            ap
@@ -408,11 +395,38 @@ QSE_EXPORT qse_ssize_t qse_putwcsvf (
 	va_list            ap
 );
 
-QSE_EXPORT qse_ssize_t qse_putstrvf (
-	const qse_char_t* fmt,
-	va_list           ap
+QSE_EXPORT qse_ssize_t qse_errputmbsf (
+	const qse_mchar_t* fmt,
+	...
 );
 
+QSE_EXPORT qse_ssize_t qse_errputwcsf (
+	const qse_wchar_t* fmt,
+	...
+);
+
+QSE_EXPORT qse_ssize_t qse_errputmbsvf (
+	const qse_mchar_t* fmt,
+	va_list            ap
+);
+
+QSE_EXPORT qse_ssize_t qse_errputwcsvf (
+	const qse_wchar_t* fmt,
+	va_list            ap
+);
+
+#if defined(QSE_CHAR_IS_MCHAR)
+#	define qse_putstrf qse_putmbsf
+#	define qse_putstrvf(fmt,ap) qse_putmbsvf(fmt,ap)
+#	define qse_errputstrf qse_errputmbsf
+#	define qse_errputstrvf(fmt,ap) qse_errputmbsvf(fmt,ap)
+#else
+#	define qse_putstrf qse_putwcsf
+#	define qse_putstrvf(fmt,ap) qse_putwcsvf(fmt,ap)
+#	define qse_errputstrf qse_errputwcsf
+#	define qse_errputstrvf(fmt,ap) qse_errputwcsvf(fmt,ap)
+#endif
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/qse/include/qse/cmn/str.h b/qse/include/qse/cmn/str.h
index c41a696e..36e8a577 100644
--- a/qse/include/qse/cmn/str.h
+++ b/qse/include/qse/cmn/str.h
@@ -712,18 +712,14 @@ QSE_EXPORT qse_size_t qse_wcsxfmt (
 	...
 );
 
-QSE_EXPORT qse_size_t qse_strfmt (
-	qse_char_t*       buf,
-	const qse_char_t* fmt,
-	...
-);
 
-QSE_EXPORT qse_size_t qse_strxfmt (
-	qse_char_t*       buf,
-	qse_size_t        bsz,
-	const qse_char_t* fmt,
-	...
-);
+#if defined(QSE_CHAR_IS_MCHAR)
+#	define qse_strfmt qse_mbsfmt
+#	define qse_strxfmt qse_mbsxfmt
+#else
+#	define qse_strfmt qse_wcsfmt
+#	define qse_strxfmt qse_wcsxfmt
+#endif
 
 /**
  * The qse_mbsxsubst() function expands \a fmt into a buffer \a buf of the size
diff --git a/qse/lib/awk/mod-sys.c b/qse/lib/awk/mod-sys.c
index 8596e476..00261360 100644
--- a/qse/lib/awk/mod-sys.c
+++ b/qse/lib/awk/mod-sys.c
@@ -43,7 +43,6 @@
 #endif
 
 #include <stdlib.h> /* getenv */
-#include <qse/cmn/stdio.h> /* qse_sprintf */
 
 static int fnc_fork (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi)
 {
@@ -552,7 +551,7 @@ static int fnc_getnwifcfg (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi)
 				md[4].key.ptr = QSE_T("ethw");
 				md[4].key.len = 4;
 				md[4].type = QSE_AWK_VAL_MAP_DATA_STR;
-				qse_sprintf (ethw, QSE_COUNTOF(ethw), QSE_T("%02X:%02X:%02X:%02X:%02X:%02X"), 
+				qse_strxfmt (ethw, QSE_COUNTOF(ethw), QSE_T("%02X:%02X:%02X:%02X:%02X:%02X"), 
 					cfg.ethw[0], cfg.ethw[1], cfg.ethw[2], cfg.ethw[3], cfg.ethw[4], cfg.ethw[5]);
 				md[4].vptr = ethw;
 
diff --git a/qse/lib/awk/run.c b/qse/lib/awk/run.c
index a669998d..a331a71e 100644
--- a/qse/lib/awk/run.c
+++ b/qse/lib/awk/run.c
@@ -22,7 +22,7 @@
 #include <qse/cmn/fmt.h>
 
 #ifdef DEBUG_RUN
-#include <qse/cmn/stdio.h>
+#include <qse/cmn/sio.h>
 #endif
 
 #define PRINT_IOERR -99
@@ -1889,7 +1889,7 @@ static int run_block0 (qse_awk_rtx_t* rtx, qse_awk_nde_blk_t* nde)
 	nlcls = nde->nlcls;
 
 #ifdef DEBUG_RUN
-	qse_dprintf (
+	qse_errputstrf (
 		QSE_T("securing space for local variables nlcls = %d\n"), 
 		(int)nlcls);
 #endif
@@ -1911,7 +1911,7 @@ static int run_block0 (qse_awk_rtx_t* rtx, qse_awk_nde_blk_t* nde)
 	}
 
 #ifdef DEBUG_RUN
-	qse_dprintf (QSE_T("executing block statements\n"));
+	qse_errputstrf (QSE_T("executing block statements\n"));
 #endif
 
 	while (p != QSE_NULL && rtx->exit_level == EXIT_NONE)
@@ -1926,7 +1926,7 @@ static int run_block0 (qse_awk_rtx_t* rtx, qse_awk_nde_blk_t* nde)
 
 	/* pop off local variables */
 #ifdef DEBUG_RUN
-	qse_dprintf (QSE_T("popping off local variables\n"));
+	qse_errputstrf (QSE_T("popping off local variables\n"));
 #endif
 	nlcls = nde->nlcls;
 	while (nlcls > 0)
@@ -3759,7 +3759,7 @@ retry:
 	if (str == QSE_NULL) return QSE_NULL;
 
 #ifdef DEBUG_RUN
-	qse_dprintf (QSE_T("**** index str=>%s, map->ref=%d, map->type=%d\n"), 
+	qse_errputstrf (QSE_T("**** index str=>%s, map->ref=%d, map->type=%d\n"), 
 		str, (int)map->ref, (int)map->type);
 #endif
 
@@ -5708,7 +5708,7 @@ static qse_awk_val_t* __eval_call (
 	saved_stack_top = run->stack_top;
 
 #ifdef DEBUG_RUN
-	qse_dprintf (QSE_T("setting up function stack frame top=%ld base=%ld\n"), 
+	qse_errputstrf (QSE_T("setting up function stack frame top=%ld base=%ld\n"), 
 		(long)run->stack_top, (long)run->stack_base);
 #endif
 	if (__raw_push(run,(void*)run->stack_base) == -1) 
@@ -5775,7 +5775,7 @@ static qse_awk_val_t* __eval_call (
 	RTX_STACK_NARGS(run) = (void*)nargs;
 	
 #ifdef DEBUG_RUN
-	qse_dprintf (QSE_T("running function body\n"));
+	qse_errputstrf (QSE_T("running function body\n"));
 #endif
 
 	if (fun != QSE_NULL)
@@ -5825,7 +5825,7 @@ static qse_awk_val_t* __eval_call (
 	/* refdown args in the run.stack */
 	nargs = (qse_size_t)RTX_STACK_NARGS(run);
 #ifdef DEBUG_RUN
-	qse_dprintf (QSE_T("block run complete nargs = %d\n"), (int)nargs); 
+	qse_errputstrf (QSE_T("block run complete nargs = %d\n"), (int)nargs); 
 #endif
 
 	for (i = 0; i < nargs; i++)
@@ -5834,7 +5834,7 @@ static qse_awk_val_t* __eval_call (
 	}
 
 #ifdef DEBUG_RUN
-	qse_dprintf (QSE_T("got return value\n"));
+	qse_errputstrf (QSE_T("got return value\n"));
 #endif
 
 	v = RTX_STACK_RETVAL(run);
@@ -5889,7 +5889,7 @@ static qse_awk_val_t* __eval_call (
 	if (run->exit_level == EXIT_FUNCTION) run->exit_level = EXIT_NONE;
 
 #ifdef DEBUG_RUN
-	qse_dprintf (QSE_T("returning from function top=%ld, base=%ld\n"),
+	qse_errputstrf (QSE_T("returning from function top=%ld, base=%ld\n"),
 		(long)run->stack_top, (long)run->stack_base); 
 #endif
 	return (n == -1)? QSE_NULL: v;
@@ -6583,7 +6583,7 @@ read_again:
 	}
 
 #ifdef DEBUG_RUN
-	qse_dprintf (QSE_T("record len = %d str=[%.*s]\n"), 
+	qse_errputstrf (QSE_T("record len = %d str=[%.*s]\n"), 
 		(int)QSE_STR_LEN(buf), (int)QSE_STR_LEN(buf), QSE_STR_PTR(buf));
 #endif
 	if (n == 0) 
diff --git a/qse/lib/awk/val.c b/qse/lib/awk/val.c
index 602e8671..0984829f 100644
--- a/qse/lib/awk/val.c
+++ b/qse/lib/awk/val.c
@@ -22,7 +22,7 @@
 #include <qse/cmn/mbwc.h>
 
 #ifdef DEBUG_VAL
-#include <qse/cmn/stdio.h>
+#include <qse/cmn/sio.h>
 #endif
 
 #define CHUNKSIZE QSE_AWK_VAL_CHUNK_SIZE
@@ -140,7 +140,7 @@ qse_awk_val_t* qse_awk_rtx_makeintval (qse_awk_rtx_t* rtx, qse_long_t v)
 	val->nde = QSE_NULL;
 
 #ifdef DEBUG_VAL
-	qse_dprintf (QSE_T("makeintval => %ld [%p]\n"), (long)v, val);
+	qse_errputstrf (QSE_T("makeintval => %ld [%p]\n"), (long)v, val);
 #endif
 	return (qse_awk_val_t*)val;
 }
@@ -196,7 +196,7 @@ qse_awk_val_t* qse_awk_rtx_makefltval (qse_awk_rtx_t* rtx, qse_flt_t v)
 	val->nde = QSE_NULL;
 
 #ifdef DEBUG_VAL
-	qse_dprintf (QSE_T("makefltval => %Lf [%p]\n"), (double)v, val);
+	qse_errputstrf (QSE_T("makefltval => %Lf [%p]\n"), (double)v, val);
 #endif
 	return (qse_awk_val_t*)val;
 }
@@ -342,7 +342,7 @@ init:
 	qse_strncpy (val->val.ptr, str->ptr, str->len);
 
 #ifdef DEBUG_VAL
-	qse_dprintf (QSE_T("makestrval => %p\n"), val);
+	qse_errputstrf (QSE_T("makestrval => %p\n"), val);
 #endif
 	return (qse_awk_val_t*)val;
 }
@@ -402,7 +402,7 @@ init:
 	qse_strncpy (&val->val.ptr[len1], str2, len2);
 
 #ifdef DEBUG_VAL
-	qse_dprintf (QSE_T("makestrval2 => %p\n"), val);
+	qse_errputstrf (QSE_T("makestrval2 => %p\n"), val);
 #endif
 	return (qse_awk_val_t*)val;
 }
@@ -477,9 +477,9 @@ static void free_mapval (qse_htb_t* map, void* dptr, qse_size_t dlen)
 	qse_awk_rtx_t* rtx = *(qse_awk_rtx_t**)QSE_XTN(map);
 
 #ifdef DEBUG_VAL
-	qse_dprintf (QSE_T("refdown in map free..."));
+	qse_errputstrf (QSE_T("refdown in map free..."));
 	qse_awk_dprintval (rtx, dptr);
-	qse_dprintf (QSE_T("\n"));
+	qse_errputstrf (QSE_T("\n"));
 #endif
 
 	qse_awk_rtx_refdownval (rtx, dptr);
@@ -489,9 +489,9 @@ static void same_mapval (qse_htb_t* map, void* dptr, qse_size_t dlen)
 {
 	qse_awk_rtx_t* run = *(qse_awk_rtx_t**)QSE_XTN(map);
 #ifdef DEBUG_VAL
-	qse_dprintf (QSE_T("refdown nofree in map free..."));
+	qse_errputstrf (QSE_T("refdown nofree in map free..."));
 	qse_awk_dprintval (run, dptr);
-	qse_dprintf (QSE_T("\n"));
+	qse_errputstrf (QSE_T("\n"));
 #endif
 	qse_awk_rtx_refdownval_nofree (run, dptr);
 }
@@ -765,9 +765,9 @@ void qse_awk_rtx_freeval (
 	if (IS_STATICVAL(val)) return;
 
 #ifdef DEBUG_VAL
-	qse_dprintf (QSE_T("freeing [cache=%d] ... "), cache);
+	qse_errputstrf (QSE_T("freeing [cache=%d] ... "), cache);
 	qse_awk_dprintval (rtx, val);
-	qse_dprintf (QSE_T("\n"));
+	qse_errputstrf (QSE_T("\n"));
 #endif
 
 	switch (val->type)
@@ -857,9 +857,9 @@ void qse_awk_rtx_refupval (qse_awk_rtx_t* rtx, qse_awk_val_t* val)
 	if (IS_STATICVAL(val)) return;
 
 #ifdef DEBUG_VAL
-	qse_dprintf (QSE_T("ref up [ptr=%p] [count=%d] "), val, (int)val->ref);
+	qse_errputstrf (QSE_T("ref up [ptr=%p] [count=%d] "), val, (int)val->ref);
 	qse_awk_dprintval (rtx, val);
-	qse_dprintf (QSE_T("\n"));
+	qse_errputstrf (QSE_T("\n"));
 #endif
 
 	val->ref++;
@@ -870,9 +870,9 @@ void qse_awk_rtx_refdownval (qse_awk_rtx_t* rtx, qse_awk_val_t* val)
 	if (IS_STATICVAL(val)) return;
 
 #ifdef DEBUG_VAL
-	qse_dprintf (QSE_T("ref down [ptr=%p] [count=%d]\n"), val, (int)val->ref);
+	qse_errputstrf (QSE_T("ref down [ptr=%p] [count=%d]\n"), val, (int)val->ref);
 	qse_awk_dprintval (rtx, val);
-	qse_dprintf (QSE_T("\n"));
+	qse_errputstrf (QSE_T("\n"));
 #endif
 
 	QSE_ASSERTX (val->ref > 0, 
@@ -1402,7 +1402,7 @@ int qse_awk_rtx_valtostr (
 
 
 #ifdef DEBUG_VAL
-	qse_dprintf (
+	qse_errputstrf (
 		QSE_T(">>WRONG VALUE TYPE [%d] in qse_awk_rtx_valtostr\n"), 
 		v->type
 	);
@@ -1569,7 +1569,7 @@ int qse_awk_rtx_valtonum (
 	}
 
 #ifdef DEBUG_VAL
-	qse_dprintf (
+	qse_errputstrf (
 		QSE_T(">>WRONG VALUE TYPE [%d] in qse_awk_rtx_valtonum()\n"),
 		v->type
 	);
@@ -1669,7 +1669,7 @@ qse_long_t qse_awk_rtx_hashval (qse_awk_rtx_t* rtx, qse_awk_val_t* v)
 		default:
 
 #ifdef DEBUG_VAL
-			qse_dprintf (
+			qse_errputstrf (
 				QSE_T(">>WRONG VALUE TYPE [%d] in qse_awk_rtx_hashval()\n"), 
 				v->type
 			);
diff --git a/qse/lib/cmn/fmt-out.c b/qse/lib/cmn/fmt-out.c
index 01ed0009..3d63c792 100644
--- a/qse/lib/cmn/fmt-out.c
+++ b/qse/lib/cmn/fmt-out.c
@@ -116,11 +116,11 @@ static const qse_wchar_t* w_hex2ascii =
 #undef ochar_t
 #undef T
 #undef OT
+#undef CONV_MAX
 #undef toupper
 #undef hex2ascii
 #undef sprintn
-#undef put_char
-#undef put_ochar
+#undef fmtout_t
 #undef fmtout
 
 #define char_t qse_mchar_t
@@ -128,10 +128,10 @@ static const qse_wchar_t* w_hex2ascii =
 #define ochar_t qse_wchar_t
 #define T(x) QSE_MT(x)
 #define OT(x) QSE_WT(x)
+#define CONV_MAX QSE_MBLEN_MAX
 #define toupper QSE_TOUPPER
 #define sprintn m_sprintn
-#define put_char put_mchar
-#define put_ochar put_wchar
+#define fmtout_t qse_mfmtout_t
 #define fmtout qse_mfmtout
 
 #define hex2ascii(hex)  (m_hex2ascii[hex])
@@ -145,11 +145,11 @@ static const qse_wchar_t* w_hex2ascii =
 #undef ochar_t
 #undef T
 #undef OT
+#undef CONV_MAX
 #undef toupper
 #undef hex2ascii
 #undef sprintn
-#undef put_char
-#undef put_ochar
+#undef fmtout_t
 #undef fmtout
 
 #define char_t qse_wchar_t
@@ -157,10 +157,10 @@ static const qse_wchar_t* w_hex2ascii =
 #define ochar_t qse_mchar_t
 #define T(x) QSE_WT(x)
 #define OT(x) QSE_MT(x)
+#define CONV_MAX 1
 #define toupper QSE_TOWUPPER
 #define sprintn w_sprintn
-#define put_char put_wchar
-#define put_ochar put_mchar
+#define fmtout_t qse_wfmtout_t
 #define fmtout qse_wfmtout
 
 #define hex2ascii(hex)  (w_hex2ascii[hex])
diff --git a/qse/lib/cmn/fmt-out.h b/qse/lib/cmn/fmt-out.h
index a1c91822..5f0b7e8a 100644
--- a/qse/lib/cmn/fmt-out.h
+++ b/qse/lib/cmn/fmt-out.h
@@ -84,21 +84,17 @@ static char_t* sprintn (char_t* nbuf, qse_uintmax_t num, int base, int *lenp, in
 /* NOTE: data output is aborted if the data limit is reached or 
  *       I/O error occurs  */
 
+#undef PUT_CHAR
+
 #define PUT_CHAR(c) do { \
 	int xx; \
 	if (data->count >= data->limit) goto done; \
-	if ((xx = data->put_char (c, data->ctx)) <= -1) goto oops; \
+	if ((xx = data->put (c, data->ctx)) <= -1) goto oops; \
+	if (xx == 0) goto done; \
 	data->count += xx; \
 } while (0)
 
-#define PUT_OCHAR(c) do { \
-	int xx; \
-	if (data->count >= data->limit) goto done; \
-	if ((xx = data->put_ochar (c, data->ctx)) <= -1) goto oops; \
-	data->count += xx; \
-} while (0)
-
-int fmtout (const char_t* fmt, qse_fmtout_t* data, va_list ap)
+int fmtout (const char_t* fmt, fmtout_t* data, va_list ap)
 {
 	char_t nbuf[MAXNBUF];
 	const char_t* p, * percent;
@@ -106,12 +102,11 @@ int fmtout (const char_t* fmt, qse_fmtout_t* data, va_list ap)
 	uchar_t ch; 
 	char_t ach, padc, * sp;
 	ochar_t oach, * osp;
+	qse_size_t oslen, slen;
 	int lm_flag, lm_dflag, flagc, numlen;
 	qse_uintmax_t num = 0;
 	int stop = 0;
 
-	data->count = 0;
-
 	struct
 	{
 		qse_mchar_t  sbuf[32];	
@@ -126,6 +121,8 @@ int fmtout (const char_t* fmt, qse_fmtout_t* data, va_list ap)
 		qse_size_t   capa;
 	} fltout;
 
+	data->count = 0;
+
 	fltfmt.ptr  = fltfmt.sbuf;
 	fltfmt.capa = QSE_COUNTOF(fltfmt.sbuf) - 1;
 
@@ -389,13 +386,36 @@ reswitch:
 		uppercase_c:
 			oach = QSE_SIZEOF(ochar_t) < QSE_SIZEOF(int)? va_arg(ap, int): va_arg(ap, ochar_t);
 
+			oslen = 1;
+			if (data->conv (&oach, &oslen, QSE_NULL, &slen, data->ctx) <= -1)
+			{
+				/* conversion error */
+				goto oops;
+			}
+
 			/* precision 0 doesn't kill the letter */
-			width--;
+			width -= slen;
 			if (!(flagc & FLAGC_LEFTADJ) && width > 0)
 			{
 				while (width--) PUT_CHAR (padc);
 			}
-			PUT_OCHAR (oach);
+
+			{
+				char_t conv_buf[CONV_MAX]; 
+				qse_size_t i, conv_len;
+
+				oslen = 1;
+				conv_len = QSE_COUNTOF(conv_buf);
+
+				/* this must not fail since the dry-run above was successful */
+				data->conv (&oach, &oslen, conv_buf, &conv_len, data->ctx);
+
+				for (i = 0; i < conv_len; i++)
+				{
+					PUT_CHAR (conv_buf[i]);
+				}
+			}
+
 			if ((flagc & FLAGC_LEFTADJ) && width > 0)
 			{
 				while (width--) PUT_CHAR (padc);
@@ -414,13 +434,11 @@ reswitch:
 		print_lowercase_s:
 			if (flagc & FLAGC_DOT)
 			{
-				for (n = 0; n < precision && sp[n]; n++) continue;
+				for (n = 0; n < precision && sp[n]; n++);
 			}
 			else
 			{
-				char_t* p = sp;
-				while (*p) p++;
-				n = p - sp;
+				for (n = 0; sp[n]; n++);
 			}
 
 			width -= n;
@@ -445,24 +463,57 @@ reswitch:
 
 			osp = va_arg (ap, ochar_t*);
 			if (osp == QSE_NULL) osp = OT("(null)");
-			if (flagc & FLAGC_DOT) 
+
+			/* get the length */
+			for (oslen = 0; osp[oslen]; oslen++);
+
+			if (data->conv (osp, &oslen, QSE_NULL, &slen, data->ctx) <= -1)
 			{
-				for (n = 0; n < precision && osp[n]; n++) continue;
-			}
-			else
-			{
-				ochar_t* p = osp;
-				while (*p) p++;
-				n = p - osp;
+				/* conversion error */
+				goto oops;
 			}
 
+			/* slen hold the length after conversion */
+			n = slen;
+			if ((flagc & FLAGC_DOT) && precision < slen) n = precision;
 			width -= n;
 
 			if (!(flagc & FLAGC_LEFTADJ) && width > 0)
 			{
 				while (width--) PUT_CHAR (padc);
 			}
-			while (n--) PUT_OCHAR(*osp++);
+
+			{
+				char_t conv_buf[CONV_MAX]; 
+				qse_size_t i, conv_len, src_len, tot_len = 0;
+				while (n > 0)
+				{
+					QSE_ASSERT (oslen > tot_len);
+
+				#if CONV_MAX == 1
+					src_len = oslen - tot_len;
+				#else
+					src_len = 1;
+				#endif
+					conv_len = QSE_COUNTOF(conv_buf);
+
+					/* this must not fail since the dry-run above was successful */
+					data->conv (&osp[tot_len], &src_len, conv_buf, &conv_len, data->ctx);
+					tot_len += src_len;
+
+					/* stop outputting if a converted character can't be printed 
+					 * in its entirety (limited by precision). but this is not an error */
+					if (n < conv_len) break; 
+
+					for (i = 0; i < conv_len; i++)
+					{
+						PUT_CHAR (conv_buf[i]);
+					}
+
+					n -= conv_len;
+				}
+			}
+			
 			if ((flagc & FLAGC_LEFTADJ) && width > 0)
 			{
 				while (width--) PUT_CHAR (padc);
@@ -754,5 +805,4 @@ oops:
 	return (qse_ssize_t)-1;
 }
 #undef PUT_CHAR
-#undef PUT_OCHAR
 
diff --git a/qse/lib/cmn/fmt.h b/qse/lib/cmn/fmt.h
index 48254441..8945958a 100644
--- a/qse/lib/cmn/fmt.h
+++ b/qse/lib/cmn/fmt.h
@@ -45,19 +45,72 @@ struct qse_fmtout_t
 
 typedef struct qse_fmtout_t qse_fmtout_t;
 
+
+
+typedef int (*qse_mfmtout_put_t) (
+	qse_mchar_t c,
+	void*       ctx
+);
+
+/* convert a wide string to a multi-byte string */
+typedef int (*qse_mfmtout_conv_t) (
+	const qse_wchar_t* wcs,
+	qse_size_t*        wcslen,
+	qse_mchar_t*       mbs,
+	qse_size_t*        mbslen,
+	void*              ctx
+);
+
+struct qse_mfmtout_t
+{
+	qse_size_t         count;     /* out */
+	qse_size_t         limit;     /* in */
+	void*              ctx;       /* in */
+	qse_mfmtout_put_t  put;       /* in */
+	qse_mfmtout_conv_t conv;      /* in */
+};
+
+typedef struct qse_mfmtout_t qse_mfmtout_t;
+
+typedef int (*qse_wfmtout_put_t) (
+	qse_wchar_t c,
+	void*       ctx
+);
+
+/* convert a multi-byte string to a wide string */
+typedef int (*qse_wfmtout_conv_t) (
+	const qse_mchar_t* mbs,
+	qse_size_t*        mbslen,
+	qse_wchar_t*       wcs,
+	qse_size_t*        wcslen,
+	void*              ctx
+);
+
+struct qse_wfmtout_t
+{
+	qse_size_t         count;     /* out */
+	qse_size_t         limit;     /* in */
+	void*              ctx;       /* in */
+	qse_wfmtout_put_t  put;       /* in */
+	qse_wfmtout_conv_t conv;      /* in */
+};
+
+
+typedef struct qse_wfmtout_t qse_wfmtout_t;
+
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 int qse_mfmtout (
 	const qse_mchar_t* fmt,
-	qse_fmtout_t*      data,
+	qse_mfmtout_t*     data,
 	va_list            ap
 );
 
 int qse_wfmtout (
 	const qse_wchar_t* fmt,
-	qse_fmtout_t*      data,
+	qse_wfmtout_t*     data,
 	va_list            ap
 );
 
diff --git a/qse/lib/cmn/sio.c b/qse/lib/cmn/sio.c
index d520f44d..77931f47 100644
--- a/qse/lib/cmn/sio.c
+++ b/qse/lib/cmn/sio.c
@@ -19,6 +19,7 @@
  */
 
 #include <qse/cmn/sio.h>
+#include <qse/cmn/mbwc.h>
 #include "mem.h"
 #include "fmt.h"
 
@@ -636,26 +637,40 @@ qse_ssize_t qse_sio_putwcsn (
 	return n;
 }
 
-static int put_wchar (qse_wchar_t c, void* arg)
+static int put_wchar (qse_wchar_t c, void* ctx)
 {
-	return qse_sio_putwc ((qse_sio_t*)arg, c);
+	return qse_sio_putwc ((qse_sio_t*)ctx, c);
 }
 
-static int put_mchar (qse_mchar_t c, void* arg)
+static int put_mchar (qse_mchar_t c, void* ctx)
 {
-	return qse_sio_putmb ((qse_sio_t*)arg, c);
+	return qse_sio_putmb ((qse_sio_t*)ctx, c);
+}
+
+static int wcs_to_mbs (
+	const qse_wchar_t* wcs, qse_size_t* wcslen,
+	qse_mchar_t* mbs, qse_size_t* mbslen, void* ctx)
+{
+	return qse_wcsntombsnwithcmgr (wcs, wcslen,  mbs, mbslen, qse_sio_getcmgr ((qse_sio_t*)ctx));
+}
+
+static int mbs_to_wcs (
+	const qse_mchar_t* mbs, qse_size_t* mbslen, 
+	qse_wchar_t* wcs, qse_size_t* wcslen, void* ctx)
+{
+	return qse_mbsntowcsnwithcmgr (mbs, mbslen, wcs, wcslen, qse_sio_getcmgr ((qse_sio_t*)ctx));
 }
 
 qse_ssize_t qse_sio_putmbsf (qse_sio_t* sio, const qse_mchar_t* fmt, ...)
 {
 	va_list ap;
 	qse_ssize_t x;
-	qse_fmtout_t fo;
+	qse_mfmtout_t fo;
 
 	fo.limit = QSE_TYPE_MAX(qse_ssize_t);
 	fo.ctx = sio;
-	fo.put_mchar = put_mchar;
-	fo.put_wchar = put_wchar;
+	fo.put = put_mchar;
+	fo.conv = wcs_to_mbs;
 
 	va_start (ap, fmt);
 	x = qse_mfmtout (fmt, &fo, ap);
@@ -668,12 +683,12 @@ qse_ssize_t qse_sio_putwcsf (qse_sio_t* sio, const qse_wchar_t* fmt, ...)
 {
 	va_list ap;
 	int x;
-	qse_fmtout_t fo;
+	qse_wfmtout_t fo;
 
 	fo.limit = QSE_TYPE_MAX(qse_ssize_t);
 	fo.ctx = sio;
-	fo.put_mchar = put_mchar;
-	fo.put_wchar = put_wchar;
+	fo.put = put_wchar;
+	fo.conv = mbs_to_wcs;
 
 	va_start (ap, fmt);
 	x = qse_wfmtout (fmt, &fo, ap);
@@ -682,60 +697,30 @@ qse_ssize_t qse_sio_putwcsf (qse_sio_t* sio, const qse_wchar_t* fmt, ...)
 	return (x <= -1)? -1: fo.count;
 }
 
-qse_ssize_t qse_sio_putstrf (qse_sio_t* sio, const qse_char_t* fmt, ...)
-{
-	va_list ap;
-	int x;
-	qse_fmtout_t fo;
-
-	fo.limit = QSE_TYPE_MAX(qse_ssize_t);
-	fo.ctx = sio;
-	fo.put_mchar = put_mchar;
-	fo.put_wchar = put_wchar;
-
-	va_start (ap, fmt);
-	x = qse_fmtout (fmt, &fo, ap);
-	va_end (ap);
-
-	return (x <= -1)? -1: fo.count;
-}
-
 qse_ssize_t qse_sio_putmbsvf (qse_sio_t* sio, const qse_mchar_t* fmt, va_list ap)
 {
-	qse_fmtout_t fo;
+	qse_mfmtout_t fo;
 
 	fo.limit = QSE_TYPE_MAX(qse_ssize_t);
 	fo.ctx = sio;
-	fo.put_mchar = put_mchar;
-	fo.put_wchar = put_wchar;
+	fo.put = put_mchar;
+	fo.conv = wcs_to_mbs;
 
 	return (qse_mfmtout (fmt, &fo, ap) <= -1)? -1: fo.count;
 }
 
 qse_ssize_t qse_sio_putwcsvf (qse_sio_t* sio, const qse_wchar_t* fmt, va_list ap)
 {
-	qse_fmtout_t fo;
+	qse_wfmtout_t fo;
 
 	fo.limit = QSE_TYPE_MAX(qse_ssize_t);
 	fo.ctx = sio;
-	fo.put_mchar = put_mchar;
-	fo.put_wchar = put_wchar;
+	fo.put = put_wchar;
+	fo.conv = mbs_to_wcs;
 
 	return (qse_wfmtout (fmt, &fo, ap) <= -1)? -1: fo.count;
 }
 
-qse_ssize_t qse_sio_putstrvf (qse_sio_t* sio, const qse_char_t* fmt, va_list ap)
-{
-	qse_fmtout_t fo;
-
-	fo.limit = QSE_TYPE_MAX(qse_ssize_t);
-	fo.ctx = sio;
-	fo.put_mchar = put_mchar;
-	fo.put_wchar = put_wchar;
-
-	return (qse_fmtout (fmt, &fo, ap) <= -1)? -1: fo.count;
-}
-
 int qse_sio_getpos (qse_sio_t* sio, qse_sio_pos_t* pos)
 {
 	qse_fio_off_t off;
@@ -875,12 +860,12 @@ qse_ssize_t qse_putmbsf (const qse_mchar_t* fmt, ...)
 {
 	va_list ap;
 	int x;
-	qse_fmtout_t fo;
+	qse_mfmtout_t fo;
 
 	fo.limit = QSE_TYPE_MAX(qse_ssize_t);
 	fo.ctx = sio_stdout;
-	fo.put_mchar = put_mchar;
-	fo.put_wchar = put_wchar;
+	fo.put = put_mchar;
+	fo.conv = wcs_to_mbs;
 
 	va_start (ap, fmt);
 	x = qse_mfmtout (fmt, &fo, ap);
@@ -893,12 +878,12 @@ qse_ssize_t qse_putwcsf (const qse_wchar_t* fmt, ...)
 {
 	va_list ap;
 	int x;
-	qse_fmtout_t fo;
+	qse_wfmtout_t fo;
 
 	fo.limit = QSE_TYPE_MAX(qse_ssize_t);
 	fo.ctx = sio_stdout;
-	fo.put_mchar = put_mchar;
-	fo.put_wchar = put_wchar;
+	fo.put = put_wchar;
+	fo.conv = mbs_to_wcs;
 
 	va_start (ap, fmt);
 	x = qse_wfmtout (fmt, &fo, ap);
@@ -907,56 +892,86 @@ qse_ssize_t qse_putwcsf (const qse_wchar_t* fmt, ...)
 	return (x <= -1)? -1: fo.count;
 }
 
-qse_ssize_t qse_putstrf (const qse_char_t* fmt, ...)
-{
-	va_list ap;
-	int x;
-	qse_fmtout_t fo;
-
-	fo.limit = QSE_TYPE_MAX(qse_ssize_t);
-	fo.ctx = sio_stdout;
-	fo.put_mchar = put_mchar;
-	fo.put_wchar = put_wchar;
-
-	va_start (ap, fmt);
-	x = qse_fmtout (fmt, &fo, ap);
-	va_end (ap);
-
-	return (x <= -1)? -1: fo.count;
-}
-
 qse_ssize_t qse_putmbsvf (const qse_mchar_t* fmt, va_list ap)
 {
-	qse_fmtout_t fo;
+	qse_mfmtout_t fo;
 
 	fo.limit = QSE_TYPE_MAX(qse_ssize_t);
 	fo.ctx = sio_stdout;
-	fo.put_mchar = put_mchar;
-	fo.put_wchar = put_wchar;
+	fo.put = put_mchar;
+	fo.conv = wcs_to_mbs;
 
 	return (qse_mfmtout (fmt, &fo, ap) <= -1)? -1: fo.count;
 }
 
 qse_ssize_t qse_putwcsvf (const qse_wchar_t* fmt, va_list ap)
 {
-	qse_fmtout_t fo;
+	qse_wfmtout_t fo;
 
 	fo.limit = QSE_TYPE_MAX(qse_ssize_t);
 	fo.ctx = sio_stdout;
-	fo.put_mchar = put_mchar;
-	fo.put_wchar = put_wchar;
+	fo.put = put_wchar;
+	fo.conv = mbs_to_wcs;
 
 	return (qse_wfmtout (fmt, &fo, ap) <= -1)? -1: fo.count;
 }
 
-qse_ssize_t qse_putstrvf (const qse_char_t* fmt, va_list ap)
+qse_ssize_t qse_errputmbsf (const qse_mchar_t* fmt, ...)
 {
-	qse_fmtout_t fo;
+	va_list ap;
+	int x;
+	qse_mfmtout_t fo;
 
 	fo.limit = QSE_TYPE_MAX(qse_ssize_t);
-	fo.ctx = sio_stdout;
-	fo.put_mchar = put_mchar;
-	fo.put_wchar = put_wchar;
+	fo.ctx = sio_stderr;
+	fo.put = put_mchar;
+	fo.conv = wcs_to_mbs;
 
-	return (qse_fmtout (fmt, &fo, ap) <= -1)? -1: fo.count;
+	va_start (ap, fmt);
+	x = qse_mfmtout (fmt, &fo, ap);
+	va_end (ap);
+
+	return (x <= -1)? -1: fo.count;
+}
+
+qse_ssize_t qse_errputwcsf (const qse_wchar_t* fmt, ...)
+{
+	va_list ap;
+	int x;
+	qse_wfmtout_t fo;
+
+	fo.limit = QSE_TYPE_MAX(qse_ssize_t);
+	fo.ctx = sio_stderr;
+	fo.put = put_wchar;
+	fo.conv = mbs_to_wcs;
+
+	va_start (ap, fmt);
+	x = qse_wfmtout (fmt, &fo, ap);
+	va_end (ap);
+
+	return (x <= -1)? -1: fo.count;
+}
+
+qse_ssize_t qse_errputmbsvf (const qse_mchar_t* fmt, va_list ap)
+{
+	qse_mfmtout_t fo;
+
+	fo.limit = QSE_TYPE_MAX(qse_ssize_t);
+	fo.ctx = sio_stderr;
+	fo.put = put_mchar;
+	fo.conv = wcs_to_mbs;
+
+	return (qse_mfmtout (fmt, &fo, ap) <= -1)? -1: fo.count;
+}
+
+qse_ssize_t qse_errputwcsvf (const qse_wchar_t* fmt, va_list ap)
+{
+	qse_wfmtout_t fo;
+
+	fo.limit = QSE_TYPE_MAX(qse_ssize_t);
+	fo.ctx = sio_stderr;
+	fo.put = put_wchar;
+	fo.conv = mbs_to_wcs;
+
+	return (qse_wfmtout (fmt, &fo, ap) <= -1)? -1: fo.count;
 }
diff --git a/qse/lib/cmn/str-fmt.c b/qse/lib/cmn/str-fmt.c
index 4034a984..b2bf7321 100644
--- a/qse/lib/cmn/str-fmt.c
+++ b/qse/lib/cmn/str-fmt.c
@@ -19,49 +19,62 @@
  */
 
 #include <qse/cmn/str.h>
+#include <qse/cmn/mbwc.h>
 #include "fmt.h"
 
-struct wbuf_t
-{
-	qse_wchar_t* ptr;
-	qse_size_t   len;
-	qse_size_t   capa;
-};
-
 struct mbuf_t
 {
 	qse_mchar_t* ptr;
 	qse_size_t   len;
 	qse_size_t   capa;
 };
-
-typedef struct wbuf_t wbuf_t;
 typedef struct mbuf_t mbuf_t;
 
-static int put_wchar_to_wbuf (qse_wchar_t c, void* arg)
+struct wbuf_t
 {
-	qse_fmtout_t* fo = (qse_fmtout_t*)arg;
-	wbuf_t* buf = (wbuf_t*)fo->ctx;
-	if (buf->len < buf->capa) buf->ptr[buf->len++] = c;
-	return 1;
+	qse_wchar_t* ptr;
+	qse_size_t   len;
+	qse_size_t   capa;
+};
+typedef struct wbuf_t wbuf_t;
+
+
+static int put_mchar (qse_mchar_t c, void* ctx)
+{
+	mbuf_t* buf = (mbuf_t*)ctx;
+	if (buf->len < buf->capa) 
+	{
+		buf->ptr[buf->len++] = c;
+		return 1;
+	}
+
+	return 0; /* stop. but no error */
 }
 
-static int put_mchar_to_mbuf (qse_mchar_t c, void* arg)
+static int put_wchar (qse_wchar_t c, void* ctx)
 {
-	qse_fmtout_t* fo = (qse_fmtout_t*)arg;
-	mbuf_t* buf = (mbuf_t*)fo->ctx;
-	if (buf->len < buf->capa) buf->ptr[buf->len++] = c;
-	return 1;
+	wbuf_t* buf = (wbuf_t*)ctx;
+	if (buf->len < buf->capa) 
+	{
+		buf->ptr[buf->len++] = c;
+		return 1;
+	}
+
+	return 0; /* stop. but no error */
 }
 
-static int put_wchar_to_mbuf (qse_wchar_t c, void* arg)
+static int wcs_to_mbs (
+	const qse_wchar_t* wcs, qse_size_t* wcslen,
+	qse_mchar_t* mbs, qse_size_t* mbslen, void* ctx)
 {
-	return 1;
+	return qse_wcsntombsnwithcmgr (wcs, wcslen, mbs, mbslen, qse_getdflcmgr());
 }
 
-static int put_mchar_to_wbuf (qse_mchar_t c, void* arg)
+static int mbs_to_wcs (
+	const qse_mchar_t* mbs, qse_size_t* mbslen, 
+	qse_wchar_t* wcs, qse_size_t* wcslen, void* ctx)
 {
-	return 1;
+	return qse_mbsntowcsnwithcmgr (mbs, mbslen, wcs, wcslen, qse_getdflcmgr());
 }
 
 /* ----------------------------------- */
@@ -69,18 +82,20 @@ static int put_mchar_to_wbuf (qse_mchar_t c, void* arg)
 #undef T
 #undef char_t
 #undef buf_t
+#undef fmtout_t
 #undef fmtout
-#undef output_char
-#undef output_ochar
+#undef put_char
+#undef conv_char
 #undef strfmt
 #undef strxfmt
 
 #define T(x) QSE_MT(x)
 #define char_t qse_mchar_t
 #define buf_t mbuf_t
+#define fmtout_t qse_mfmtout_t
 #define fmtout qse_mfmtout
-#define output_mchar put_mchar_to_mbuf
-#define output_wchar put_wchar_to_mbuf
+#define put_char put_mchar
+#define conv_char wcs_to_mbs
 #define strfmt qse_mbsfmt
 #define strxfmt qse_mbsxfmt
 #include "str-fmt.h"
@@ -90,47 +105,21 @@ static int put_mchar_to_wbuf (qse_mchar_t c, void* arg)
 #undef T
 #undef char_t
 #undef buf_t
+#undef fmtout_t
 #undef fmtout
-#undef output_mchar
-#undef output_wchar
+#undef put_char
+#undef conv_char
 #undef strfmt
 #undef strxfmt
 
 #define T(x) QSE_WT(x)
 #define char_t qse_wchar_t
 #define buf_t wbuf_t
+#define fmtout_t qse_wfmtout_t
 #define fmtout qse_wfmtout
-#define output_mchar put_mchar_to_wbuf
-#define output_wchar put_wchar_to_wbuf
-#define strfmtx qse_wcsfmt
-#define strxfmtx qse_wcsxfmt
+#define put_char put_wchar
+#define conv_char mbs_to_wcs
+#define strfmt qse_wcsfmt
+#define strxfmt qse_wcsxfmt
 #include "str-fmt.h"
 
-
-/* ----------------------------------- */
-
-#undef T
-#undef char_t
-#undef buf_t
-#undef fmtout
-#undef output_mchar
-#undef output_wchar
-#undef strfmt
-#undef strxfmt
-
-#define T(x) QSE_T(x)
-#define char_t qse_char_t
-#if defined(QSE_CHAR_IS_MCHAR)
-#	define buf_t mbuf_t
-#	define output_mchar put_mchar_to_mbuf
-#	define output_wchar put_wchar_to_mbuf
-#	define fmtout qse_mfmtout
-#else
-#	define buf_t wbuf_t
-#	define output_mchar put_mchar_to_wbuf
-#	define output_wchar put_wchar_to_wbuf
-#	define fmtout qse_wfmtout
-#endif
-#define strfmt qse_strfmt
-#define strxfmt qse_strxfmt
-#include "str-fmt.h"
diff --git a/qse/lib/cmn/str-fmt.h b/qse/lib/cmn/str-fmt.h
index 9517b396..8d7d523d 100644
--- a/qse/lib/cmn/str-fmt.h
+++ b/qse/lib/cmn/str-fmt.h
@@ -23,7 +23,7 @@ qse_size_t strfmt (char_t* buf, const char_t* fmt, ...)
 {
 	buf_t b;
 	va_list ap;
-	qse_fmtout_t fo;
+	fmtout_t fo;
 
 	b.ptr = buf;
 	b.len = 0;
@@ -31,8 +31,8 @@ qse_size_t strfmt (char_t* buf, const char_t* fmt, ...)
 
 	fo.limit = QSE_TYPE_MAX(qse_size_t) - 1;
 	fo.ctx = &b;
-	fo.put_mchar = output_mchar;
-	fo.put_wchar = output_wchar;
+	fo.put = put_char;
+	fo.conv = conv_char;
 
 	/* no error must be returned by fmtout since
 	 * the callback function never fails. */
@@ -42,14 +42,15 @@ qse_size_t strfmt (char_t* buf, const char_t* fmt, ...)
 
 	b.ptr[b.len] = T('\0');
 
-	return fo.count;
+	/*return fo.count;*/
+	return b.len;
 }
 
 qse_size_t strxfmt (char_t* buf, qse_size_t len, const char_t* fmt, ...)
 {
 	buf_t b;
 	va_list ap;
-	qse_fmtout_t fo;
+	fmtout_t fo;
 
 	b.ptr = buf;
 	b.len = 0;
@@ -63,8 +64,8 @@ qse_size_t strxfmt (char_t* buf, qse_size_t len, const char_t* fmt, ...)
 
 	fo.limit = QSE_TYPE_MAX(qse_size_t) - 1;
 	fo.ctx = &b;
-	fo.put_mchar = output_mchar;
-	fo.put_wchar = output_wchar;
+	fo.put = put_char;
+	fo.conv = conv_char;
 
 	/* no error must be returned by fmtout since
 	 * the callback function never fails. */
@@ -74,6 +75,7 @@ qse_size_t strxfmt (char_t* buf, qse_size_t len, const char_t* fmt, ...)
 
 	if (len > 0) b.ptr[b.len] = T('\0');
 
-	return fo.count;
+	/*return fo.count;*/
+	return b.len;
 }