diff --git a/stix/lib/Makefile.am b/stix/lib/Makefile.am
index d4bc79e..2200cf9 100644
--- a/stix/lib/Makefile.am
+++ b/stix/lib/Makefile.am
@@ -43,6 +43,7 @@ libstix_la_SOURCES = \
 	decode.c \
 	dic.c \
 	exec.c \
+	fmt.c \
 	gc.c \
 	heap.c \
 	ignite.c \
@@ -83,17 +84,17 @@ LIBADD_MOD_COMMON = -lstix
 
 pkgmodexecdir = $(libdir)
 
-pkgmodexec_LTLIBRARIES = libstix-snd.la libstix-con.la
+pkgmodexec_LTLIBRARIES = libstix-snd.la #libstix-con.la
 
 libstix_snd_la_SOURCES = mod-snd.c mod-snd.h
 libstix_snd_la_CPPFLAGS = $(CPPFLAGS_MOD_COMMON)
 libstix_snd_la_LDFLAGS = $(LDFLAGS_MOD_COMMON)
 libstix_snd_la_LIBADD = $(LIBADD_MOD_COMMON)
 
-libstix_con_la_SOURCES = mod-con.c mod-con.h
-libstix_con_la_CPPFLAGS = $(CPPFLAGS_MOD_COMMON)
-libstix_con_la_LDFLAGS = $(LDFLAGS_MOD_COMMON)
-libstix_con_la_LIBADD = $(LIBADD_MOD_COMMON)
+#libstix_con_la_SOURCES = mod-con.c mod-con.h
+#libstix_con_la_CPPFLAGS = $(CPPFLAGS_MOD_COMMON)
+#libstix_con_la_LDFLAGS = $(LDFLAGS_MOD_COMMON)
+#libstix_con_la_LIBADD = $(LIBADD_MOD_COMMON)
 
 endif
 
diff --git a/stix/lib/Makefile.in b/stix/lib/Makefile.in
index 6a37ef1..107e36b 100644
--- a/stix/lib/Makefile.in
+++ b/stix/lib/Makefile.in
@@ -133,28 +133,16 @@ am__installdirs = "$(DESTDIR)$(pkglibdir)" \
 	"$(DESTDIR)$(pkgincludedir)"
 LTLIBRARIES = $(pkglib_LTLIBRARIES) $(pkgmodexec_LTLIBRARIES)
 am__DEPENDENCIES_1 =
-@ENABLE_STATIC_MODULE_FALSE@libstix_con_la_DEPENDENCIES =  \
-@ENABLE_STATIC_MODULE_FALSE@	$(am__DEPENDENCIES_1)
-am__libstix_con_la_SOURCES_DIST = mod-con.c mod-con.h
-@ENABLE_STATIC_MODULE_FALSE@am_libstix_con_la_OBJECTS =  \
-@ENABLE_STATIC_MODULE_FALSE@	libstix_con_la-mod-con.lo
-libstix_con_la_OBJECTS = $(am_libstix_con_la_OBJECTS)
-AM_V_lt = $(am__v_lt_@AM_V@)
-am__v_lt_ = $(am__v_lt_@AM_DEFAULT_V@)
-am__v_lt_0 = --silent
-am__v_lt_1 = 
-libstix_con_la_LINK = $(LIBTOOL) $(AM_V_lt) --tag=CC \
-	$(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=link $(CCLD) \
-	$(AM_CFLAGS) $(CFLAGS) $(libstix_con_la_LDFLAGS) $(LDFLAGS) -o \
-	$@
-@ENABLE_STATIC_MODULE_FALSE@am_libstix_con_la_rpath = -rpath \
-@ENABLE_STATIC_MODULE_FALSE@	$(pkgmodexecdir)
 @ENABLE_STATIC_MODULE_FALSE@libstix_snd_la_DEPENDENCIES =  \
 @ENABLE_STATIC_MODULE_FALSE@	$(am__DEPENDENCIES_1)
 am__libstix_snd_la_SOURCES_DIST = mod-snd.c mod-snd.h
 @ENABLE_STATIC_MODULE_FALSE@am_libstix_snd_la_OBJECTS =  \
 @ENABLE_STATIC_MODULE_FALSE@	libstix_snd_la-mod-snd.lo
 libstix_snd_la_OBJECTS = $(am_libstix_snd_la_OBJECTS)
+AM_V_lt = $(am__v_lt_@AM_V@)
+am__v_lt_ = $(am__v_lt_@AM_DEFAULT_V@)
+am__v_lt_0 = --silent
+am__v_lt_1 = 
 libstix_snd_la_LINK = $(LIBTOOL) $(AM_V_lt) --tag=CC \
 	$(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=link $(CCLD) \
 	$(AM_CFLAGS) $(CFLAGS) $(libstix_snd_la_LDFLAGS) $(LDFLAGS) -o \
@@ -165,10 +153,10 @@ am__DEPENDENCIES_2 = $(am__DEPENDENCIES_1) $(am__DEPENDENCIES_1)
 libstix_la_DEPENDENCIES = $(am__DEPENDENCIES_2)
 am_libstix_la_OBJECTS = libstix_la-bigint.lo libstix_la-comp.lo \
 	libstix_la-debug.lo libstix_la-decode.lo libstix_la-dic.lo \
-	libstix_la-exec.lo libstix_la-gc.lo libstix_la-heap.lo \
-	libstix_la-ignite.lo libstix_la-obj.lo libstix_la-proc.lo \
-	libstix_la-rbt.lo libstix_la-stix.lo libstix_la-sym.lo \
-	libstix_la-utf8.lo libstix_la-utl.lo
+	libstix_la-exec.lo libstix_la-fmt.lo libstix_la-gc.lo \
+	libstix_la-heap.lo libstix_la-ignite.lo libstix_la-obj.lo \
+	libstix_la-proc.lo libstix_la-rbt.lo libstix_la-stix.lo \
+	libstix_la-sym.lo libstix_la-utf8.lo libstix_la-utl.lo
 libstix_la_OBJECTS = $(am_libstix_la_OBJECTS)
 libstix_la_LINK = $(LIBTOOL) $(AM_V_lt) --tag=CC $(AM_LIBTOOLFLAGS) \
 	$(LIBTOOLFLAGS) --mode=link $(CCLD) $(AM_CFLAGS) $(CFLAGS) \
@@ -214,11 +202,10 @@ AM_V_CCLD = $(am__v_CCLD_@AM_V@)
 am__v_CCLD_ = $(am__v_CCLD_@AM_DEFAULT_V@)
 am__v_CCLD_0 = @echo "  CCLD    " $@;
 am__v_CCLD_1 = 
-SOURCES = $(libstix_con_la_SOURCES) $(libstix_snd_la_SOURCES) \
-	$(libstix_la_SOURCES) $(stix_SOURCES)
-DIST_SOURCES = $(am__libstix_con_la_SOURCES_DIST) \
-	$(am__libstix_snd_la_SOURCES_DIST) $(libstix_la_SOURCES) \
+SOURCES = $(libstix_snd_la_SOURCES) $(libstix_la_SOURCES) \
 	$(stix_SOURCES)
+DIST_SOURCES = $(am__libstix_snd_la_SOURCES_DIST) \
+	$(libstix_la_SOURCES) $(stix_SOURCES)
 am__can_run_installinfo = \
   case $$AM_UPDATE_INFO_DIR in \
     n|no|NO) false;; \
@@ -438,6 +425,7 @@ libstix_la_SOURCES = \
 	decode.c \
 	dic.c \
 	exec.c \
+	fmt.c \
 	gc.c \
 	heap.c \
 	ignite.c \
@@ -471,15 +459,11 @@ stix_LDADD = $(LIBADD_LIB_COMMON) -lstix #-ldyncall_s
 @ENABLE_STATIC_MODULE_FALSE@LDFLAGS_MOD_COMMON = $(LDFLAGS_LIB_COMMON)
 @ENABLE_STATIC_MODULE_FALSE@LIBADD_MOD_COMMON = -lstix
 @ENABLE_STATIC_MODULE_FALSE@pkgmodexecdir = $(libdir)
-@ENABLE_STATIC_MODULE_FALSE@pkgmodexec_LTLIBRARIES = libstix-snd.la libstix-con.la
+@ENABLE_STATIC_MODULE_FALSE@pkgmodexec_LTLIBRARIES = libstix-snd.la #libstix-con.la
 @ENABLE_STATIC_MODULE_FALSE@libstix_snd_la_SOURCES = mod-snd.c mod-snd.h
 @ENABLE_STATIC_MODULE_FALSE@libstix_snd_la_CPPFLAGS = $(CPPFLAGS_MOD_COMMON)
 @ENABLE_STATIC_MODULE_FALSE@libstix_snd_la_LDFLAGS = $(LDFLAGS_MOD_COMMON)
 @ENABLE_STATIC_MODULE_FALSE@libstix_snd_la_LIBADD = $(LIBADD_MOD_COMMON)
-@ENABLE_STATIC_MODULE_FALSE@libstix_con_la_SOURCES = mod-con.c mod-con.h
-@ENABLE_STATIC_MODULE_FALSE@libstix_con_la_CPPFLAGS = $(CPPFLAGS_MOD_COMMON)
-@ENABLE_STATIC_MODULE_FALSE@libstix_con_la_LDFLAGS = $(LDFLAGS_MOD_COMMON)
-@ENABLE_STATIC_MODULE_FALSE@libstix_con_la_LIBADD = $(LIBADD_MOD_COMMON)
 all: stix-cfg.h
 	$(MAKE) $(AM_MAKEFLAGS) all-am
 
@@ -601,9 +585,6 @@ clean-pkgmodexecLTLIBRARIES:
 	  rm -f $${locs}; \
 	}
 
-libstix-con.la: $(libstix_con_la_OBJECTS) $(libstix_con_la_DEPENDENCIES) $(EXTRA_libstix_con_la_DEPENDENCIES) 
-	$(AM_V_CCLD)$(libstix_con_la_LINK) $(am_libstix_con_la_rpath) $(libstix_con_la_OBJECTS) $(libstix_con_la_LIBADD) $(LIBS)
-
 libstix-snd.la: $(libstix_snd_la_OBJECTS) $(libstix_snd_la_DEPENDENCIES) $(EXTRA_libstix_snd_la_DEPENDENCIES) 
 	$(AM_V_CCLD)$(libstix_snd_la_LINK) $(am_libstix_snd_la_rpath) $(libstix_snd_la_OBJECTS) $(libstix_snd_la_LIBADD) $(LIBS)
 
@@ -669,13 +650,13 @@ mostlyclean-compile:
 distclean-compile:
 	-rm -f *.tab.c
 
-@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libstix_con_la-mod-con.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libstix_la-bigint.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libstix_la-comp.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libstix_la-debug.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libstix_la-decode.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libstix_la-dic.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libstix_la-exec.Plo@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libstix_la-fmt.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libstix_la-gc.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libstix_la-heap.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/libstix_la-ignite.Plo@am__quote@
@@ -713,13 +694,6 @@ distclean-compile:
 @AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
 @am__fastdepCC_FALSE@	$(AM_V_CC@am__nodep@)$(LTCOMPILE) -c -o $@ $<
 
-libstix_con_la-mod-con.lo: mod-con.c
-@am__fastdepCC_TRUE@	$(AM_V_CC)$(LIBTOOL) $(AM_V_lt) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(libstix_con_la_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT libstix_con_la-mod-con.lo -MD -MP -MF $(DEPDIR)/libstix_con_la-mod-con.Tpo -c -o libstix_con_la-mod-con.lo `test -f 'mod-con.c' || echo '$(srcdir)/'`mod-con.c
-@am__fastdepCC_TRUE@	$(AM_V_at)$(am__mv) $(DEPDIR)/libstix_con_la-mod-con.Tpo $(DEPDIR)/libstix_con_la-mod-con.Plo
-@AMDEP_TRUE@@am__fastdepCC_FALSE@	$(AM_V_CC)source='mod-con.c' object='libstix_con_la-mod-con.lo' libtool=yes @AMDEPBACKSLASH@
-@AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
-@am__fastdepCC_FALSE@	$(AM_V_CC@am__nodep@)$(LIBTOOL) $(AM_V_lt) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(libstix_con_la_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o libstix_con_la-mod-con.lo `test -f 'mod-con.c' || echo '$(srcdir)/'`mod-con.c
-
 libstix_snd_la-mod-snd.lo: mod-snd.c
 @am__fastdepCC_TRUE@	$(AM_V_CC)$(LIBTOOL) $(AM_V_lt) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(libstix_snd_la_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT libstix_snd_la-mod-snd.lo -MD -MP -MF $(DEPDIR)/libstix_snd_la-mod-snd.Tpo -c -o libstix_snd_la-mod-snd.lo `test -f 'mod-snd.c' || echo '$(srcdir)/'`mod-snd.c
 @am__fastdepCC_TRUE@	$(AM_V_at)$(am__mv) $(DEPDIR)/libstix_snd_la-mod-snd.Tpo $(DEPDIR)/libstix_snd_la-mod-snd.Plo
@@ -769,6 +743,13 @@ libstix_la-exec.lo: exec.c
 @AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
 @am__fastdepCC_FALSE@	$(AM_V_CC@am__nodep@)$(LIBTOOL) $(AM_V_lt) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(libstix_la_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o libstix_la-exec.lo `test -f 'exec.c' || echo '$(srcdir)/'`exec.c
 
+libstix_la-fmt.lo: fmt.c
+@am__fastdepCC_TRUE@	$(AM_V_CC)$(LIBTOOL) $(AM_V_lt) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(libstix_la_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT libstix_la-fmt.lo -MD -MP -MF $(DEPDIR)/libstix_la-fmt.Tpo -c -o libstix_la-fmt.lo `test -f 'fmt.c' || echo '$(srcdir)/'`fmt.c
+@am__fastdepCC_TRUE@	$(AM_V_at)$(am__mv) $(DEPDIR)/libstix_la-fmt.Tpo $(DEPDIR)/libstix_la-fmt.Plo
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	$(AM_V_CC)source='fmt.c' object='libstix_la-fmt.lo' libtool=yes @AMDEPBACKSLASH@
+@AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+@am__fastdepCC_FALSE@	$(AM_V_CC@am__nodep@)$(LIBTOOL) $(AM_V_lt) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(libstix_la_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o libstix_la-fmt.lo `test -f 'fmt.c' || echo '$(srcdir)/'`fmt.c
+
 libstix_la-gc.lo: gc.c
 @am__fastdepCC_TRUE@	$(AM_V_CC)$(LIBTOOL) $(AM_V_lt) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(libstix_la_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT libstix_la-gc.lo -MD -MP -MF $(DEPDIR)/libstix_la-gc.Tpo -c -o libstix_la-gc.lo `test -f 'gc.c' || echo '$(srcdir)/'`gc.c
 @am__fastdepCC_TRUE@	$(AM_V_at)$(am__mv) $(DEPDIR)/libstix_la-gc.Tpo $(DEPDIR)/libstix_la-gc.Plo
@@ -1098,6 +1079,11 @@ uninstall-am: uninstall-binPROGRAMS uninstall-pkgincludeHEADERS \
 	uninstall-pkglibLTLIBRARIES uninstall-pkgmodexecLTLIBRARIES
 
 
+#libstix_con_la_SOURCES = mod-con.c mod-con.h
+#libstix_con_la_CPPFLAGS = $(CPPFLAGS_MOD_COMMON)
+#libstix_con_la_LDFLAGS = $(LDFLAGS_MOD_COMMON)
+#libstix_con_la_LIBADD = $(LIBADD_MOD_COMMON)
+
 install-data-hook:
 	@echo "#ifndef _STIX_CFG_H_" > "$(DESTDIR)$(pkgincludedir)/stix-cfg.h"
 	@echo "#define _STIX_CFG_H_" >> "$(DESTDIR)$(pkgincludedir)/stix-cfg.h"
diff --git a/stix/lib/comp.c b/stix/lib/comp.c
index 07e62a9..65e5042 100644
--- a/stix/lib/comp.c
+++ b/stix/lib/comp.c
@@ -4310,7 +4310,7 @@ the compiler must collect all source method string collected so far.
 need to write code to collect string.
 */
 
-	/* TODO: if (decoding is enabled... */
+	/* TODO: call stix_decode only if decoding is enabled... */
 printf (">>>> BYTE CODE.....\n");
 	stix_decode (stix, mth);
 
@@ -4374,6 +4374,7 @@ static int compile_method_definition (stix_t* stix)
 printf (">>METHOD ");
 print_oocs (&stix->c->mth.name);
 printf ("\n");
+
 	if (stix->c->tok.type != STIX_IOTOK_LBRACE)
 	{
 		/* { expected */
diff --git a/stix/lib/debug.c b/stix/lib/debug.c
index f40e407..11f4404 100644
--- a/stix/lib/debug.c
+++ b/stix/lib/debug.c
@@ -87,41 +87,28 @@ void print_object (stix_t* stix, stix_oop_t oop)
 {
 	if (oop == stix->_nil)
 	{
-		printf ("nil");
+		stix_bfmtout (stix, "nil");
 	}
 	else if (oop == stix->_true)
 	{
-		printf ("true");
+		stix_bfmtout (stix, "true");
 	}
 	else if (oop == stix->_false)
 	{
-		printf ("false");
+		stix_bfmtout (stix, "false");
 	}
 	else if (STIX_OOP_IS_SMOOI(oop))
 	{
-		printf ("%ld", (long int)STIX_OOP_TO_SMOOI(oop));
+		stix_bfmtout (stix, "%zd", STIX_OOP_TO_SMOOI(oop));
 	}
 	else if (STIX_OOP_IS_CHAR(oop))
 	{
-		stix_bch_t bcs[32];
-		stix_uch_t uch;
-		stix_oow_t ucslen, bcslen;
-
-		uch = STIX_OOP_TO_CHAR(oop);
-		bcslen = STIX_COUNTOF(bcs);
-		ucslen = 1;
-		if (stix_ucstoutf8 (&uch, &ucslen, bcs, &bcslen) >= 0)
-		{
-			printf ("$%.*s", (int)bcslen, bcs);
-		}
+		stix_bfmtout (stix, "$%.1C", STIX_OOP_TO_CHAR(oop));
 	}
 	else
 	{
 		stix_oop_class_t c;
-		stix_oocs_t s;
 		stix_oow_t i;
-		stix_bch_t bcs[32];
-		stix_oow_t ucslen, bcslen;
 
 		STIX_ASSERT (STIX_OOP_IS_POINTER(oop));
 		c = (stix_oop_class_t)STIX_OBJ_GET_CLASS(oop); /*STIX_CLASSOF(stix, oop);*/
@@ -129,95 +116,75 @@ void print_object (stix_t* stix, stix_oop_t oop)
 		if ((stix_oop_t)c == stix->_large_negative_integer)
 		{
 			stix_oow_t i;
-			printf ("-16r");
+			stix_bfmtout (stix, "-16r");
 			for (i = STIX_OBJ_GET_SIZE(oop); i > 0;)
 			{
-				printf ("%0*lX", (int)(STIX_SIZEOF(stix_liw_t) * 2), (unsigned long)((stix_oop_liword_t)oop)->slot[--i]);
+				stix_bfmtout (stix, "%0*lX", (int)(STIX_SIZEOF(stix_liw_t) * 2), (unsigned long)((stix_oop_liword_t)oop)->slot[--i]);
 			}
 		}
 		else if ((stix_oop_t)c == stix->_large_positive_integer)
 		{
 			stix_oow_t i;
-			printf ("16r");
+			stix_bfmtout (stix, "16r");
 			for (i = STIX_OBJ_GET_SIZE(oop); i > 0;)
 			{
-				printf ("%0*lX", (int)(STIX_SIZEOF(stix_liw_t) * 2), (unsigned long)((stix_oop_liword_t)oop)->slot[--i]);
+				stix_bfmtout (stix, "%0*lX", (int)(STIX_SIZEOF(stix_liw_t) * 2), (unsigned long)((stix_oop_liword_t)oop)->slot[--i]);
 			}
 		}
 		else if (STIX_OBJ_GET_FLAGS_TYPE(oop) == STIX_OBJ_TYPE_CHAR)
 		{
-			if ((stix_oop_t)c == stix->_symbol) printf ("#");
-			else if ((stix_oop_t)c == stix->_string) printf ("'");
+			if ((stix_oop_t)c == stix->_symbol) stix_bfmtout (stix, "#");
+			else if ((stix_oop_t)c == stix->_string) stix_bfmtout (stix, "'");
 
-			for (i = 0; i < STIX_OBJ_GET_SIZE(oop); i++)
-			{
-				bcslen = STIX_COUNTOF(bcs);
-				ucslen = 1;
-				if (stix_ucstoutf8 (&((stix_oop_char_t)oop)->slot[i], &ucslen, bcs, &bcslen) >= 0)
-				{
-					printf ("%.*s", (int)bcslen, bcs);
-				}
-			}
-			if ((stix_oop_t)c == stix->_string) printf ("'");
+			stix_bfmtout (stix, "%.*S", STIX_OBJ_GET_SIZE(oop), ((stix_oop_char_t)oop)->slot);
+			if ((stix_oop_t)c == stix->_string) stix_bfmtout (stix, "'");
 		}
 		else if (STIX_OBJ_GET_FLAGS_TYPE(oop) == STIX_OBJ_TYPE_BYTE)
 		{
-			printf ("#[");
+			stix_bfmtout (stix, "#[");
 			for (i = 0; i < STIX_OBJ_GET_SIZE(oop); i++)
 			{
-				printf (" %d", ((stix_oop_byte_t)oop)->slot[i]);
+				stix_bfmtout (stix, " %d", ((stix_oop_byte_t)oop)->slot[i]);
 			}
-			printf ("]");
+			stix_bfmtout (stix, "]");
 		}
 		
 		else if (STIX_OBJ_GET_FLAGS_TYPE(oop) == STIX_OBJ_TYPE_HALFWORD)
 		{
-			printf ("#[["); /* TODO: fix this symbol */
+			stix_bfmtout (stix, "#[["); /* TODO: fix this symbol */
 			for (i = 0; i < STIX_OBJ_GET_SIZE(oop); i++)
 			{
-				printf (" %lX", (unsigned long int)((stix_oop_halfword_t)oop)->slot[i]);
+				stix_bfmtout (stix, " %zX", (stix_oow_t)((stix_oop_halfword_t)oop)->slot[i]);
 			}
-			printf ("]]");
+			stix_bfmtout (stix, "]]");
 		}
 		else if (STIX_OBJ_GET_FLAGS_TYPE(oop) == STIX_OBJ_TYPE_WORD)
 		{
-			printf ("#[[["); /* TODO: fix this symbol */
+			stix_bfmtout (stix, "#[[["); /* TODO: fix this symbol */
 			for (i = 0; i < STIX_OBJ_GET_SIZE(oop); i++)
 			{
-				printf (" %lX", (unsigned long int)((stix_oop_word_t)oop)->slot[i]);
+				stix_bfmtout (stix, " %zX", ((stix_oop_word_t)oop)->slot[i]);
 			}
-			printf ("]]]");
+			stix_bfmtout (stix, "]]]");
 		}
 		else if ((stix_oop_t)c == stix->_array)
 		{
-			printf ("#(");
+			stix_bfmtout (stix, "#(");
 			for (i = 0; i < STIX_OBJ_GET_SIZE(oop); i++)
 			{
-				printf (" ");
+				stix_bfmtout (stix, " ");
 				print_object (stix, ((stix_oop_oop_t)oop)->slot[i]);
 			}
-			printf (")");
+			stix_bfmtout (stix, ")");
 		}
 		else if ((stix_oop_t)c == stix->_class)
 		{
 			/* print the class name */
-			for (i = 0; i < STIX_OBJ_GET_SIZE(((stix_oop_class_t)oop)->name); i++)
-			{
-				bcslen = STIX_COUNTOF(bcs);
-				ucslen = 1;
-				if (stix_ucstoutf8 (&((stix_oop_class_t)oop)->name->slot[i], &ucslen, bcs, &bcslen) >= 0)
-				{
-					printf ("%.*s", (int)bcslen, bcs);
-				}
-			}
+			stix_bfmtout (stix, "%.*S", STIX_OBJ_GET_SIZE(((stix_oop_class_t)oop)->name), ((stix_oop_class_t)oop)->name->slot);
 		}
 		else
 		{
-			s.ptr = ((stix_oop_char_t)c->name)->slot;
-			s.len = STIX_OBJ_GET_SIZE(c->name);
-			printf ("instance of ");
-			print_oocs (&s);
-			printf ("- (%p)", oop);
+			stix_bfmtout (stix, "instance of %.*S - (%p)", STIX_OBJ_GET_SIZE(c->name), ((stix_oop_char_t)c->name)->slot, oop);
 		}
 	}
 }
diff --git a/stix/lib/decode.c b/stix/lib/decode.c
index e44811f..44dcc04 100644
--- a/stix/lib/decode.c
+++ b/stix/lib/decode.c
@@ -26,10 +26,11 @@
 
 #include "stix-prv.h"
 
-#	define DECODE_OUT_0(fmt) printf("\t" fmt "\n")
-#	define DECODE_OUT_1(fmt,a1) printf("\t" fmt "\n",a1)
-#	define DECODE_OUT_2(fmt,a1,a2) printf("\t" fmt "\n", a1, a2)
-#	define DECODE_OUT_3(fmt,a1,a2,a3) printf("\t" fmt "\n", a1, a2, a3)
+#	define DECODE_OUT_0(stix,fmt) stix_bfmtout(stix, "\t" fmt "\n")
+#	define DECODE_OUT_1(stix,fmt,a1) stix_bfmtout(stix, "\t" fmt "\n",a1)
+#	define DECODE_OUT_2(stix,fmt,a1,a2) stix_bfmtout(stix, "\t" fmt "\n", a1, a2)
+#	define DECODE_OUT_3(stix,fmt,a1,a2,a3) stix_bfmtout(stix, "\t" fmt "\n", a1, a2, a3)
+
 
 
 #define FETCH_BYTE_CODE(stix) (cdptr[ip++])
@@ -44,8 +45,11 @@
 #	define FETCH_PARAM_CODE_TO(stix,v_ooi) (v_ooi = FETCH_BYTE_CODE(stix))
 #endif
 
+
+
+
 /* TODO: check if ip shoots beyond the maximum length in fetching code and parameters */
-static int decode (stix_t* stix, stix_oop_method_t mth)
+int stix_decode (stix_t* stix, stix_oop_method_t mth)
 {
 	stix_oob_t bcode, * cdptr;
 	stix_oow_t ip = 0, cdlen;
@@ -74,7 +78,7 @@ static int decode (stix_t* stix, stix_oop_method_t mth)
 			case BCODE_PUSH_INSTVAR_7:
 				b1 = bcode & 0x7; /* low 3 bits */
 			push_instvar:
-				DECODE_OUT_1 ("push_instvar %lu", (unsigned long int)b1);
+				DECODE_OUT_1 (stix, "push_instvar %zd", b1);
 				break;
 
 			/* ------------------------------------------------- */
@@ -92,7 +96,7 @@ static int decode (stix_t* stix, stix_oop_method_t mth)
 			case BCODE_STORE_INTO_INSTVAR_7:
 				b1 = bcode & 0x7; /* low 3 bits */
 			store_instvar:
-				DECODE_OUT_1 ("store_into_instvar %lu", (unsigned long int)b1);
+				DECODE_OUT_1 (stix, "store_into_instvar %zd", b1);
 				break;
 
 			case BCODE_POP_INTO_INSTVAR_X:
@@ -108,7 +112,7 @@ static int decode (stix_t* stix, stix_oop_method_t mth)
 			case BCODE_POP_INTO_INSTVAR_7:
 				b1 = bcode & 0x7; /* low 3 bits */
 			pop_into_instvar:
-				DECODE_OUT_1 ("pop_into_instvar %lu", (unsigned long int)b1);
+				DECODE_OUT_1 (stix, "pop_into_instvar %zd", b1);
 				break;
 
 			/* ------------------------------------------------- */
@@ -148,7 +152,7 @@ static int decode (stix_t* stix, stix_oop_method_t mth)
 				if ((bcode >> 4) & 1)
 				{
 					/* push - bit 4 on */
-					DECODE_OUT_1 ("push_tempvar %d", (int)b1);
+					DECODE_OUT_1 (stix, "push_tempvar %zd", b1);
 				}
 				else
 				{
@@ -156,11 +160,11 @@ static int decode (stix_t* stix, stix_oop_method_t mth)
 					if ((bcode >> 3) & 1)
 					{
 						/* pop - bit 3 on */
-						DECODE_OUT_1 ("pop_into_tempvar %d", (int)b1);
+						DECODE_OUT_1 (stix, "pop_into_tempvar %zd", b1);
 					}
 					else
 					{
-						DECODE_OUT_1 ("store_into_tempvar %d", (int)b1);
+						DECODE_OUT_1 (stix, "store_into_tempvar %zd", b1);
 					}
 				}
 				break;
@@ -180,7 +184,7 @@ static int decode (stix_t* stix, stix_oop_method_t mth)
 			case BCODE_PUSH_LITERAL_7:
 				b1 = bcode & 0x7; /* low 3 bits */
 			push_literal:
-				DECODE_OUT_1 ("push_literal %d", (int)b1);
+				DECODE_OUT_1 (stix, "push_literal %zd", b1);
 				break;
 
 			/* ------------------------------------------------- */
@@ -208,16 +212,16 @@ static int decode (stix_t* stix, stix_oop_method_t mth)
 				{
 					if ((bcode >> 2) & 1)
 					{
-						DECODE_OUT_1("pop_into_object %d", (int)b1);
+						DECODE_OUT_1 (stix, "pop_into_object %zd", b1);
 					}
 					else
 					{
-						DECODE_OUT_1("store_into_object %d", (int)b1);
+						DECODE_OUT_1 (stix, "store_into_object %zd", b1);
 					}
 				}
 				else
 				{
-					DECODE_OUT_1("push_object %d", (int)b1);
+					DECODE_OUT_1 (stix, "push_object %zd", b1);
 				}
 				break;
 
@@ -225,19 +229,19 @@ static int decode (stix_t* stix, stix_oop_method_t mth)
 
 			case BCODE_JUMP_FORWARD_X:
 				FETCH_PARAM_CODE_TO (stix, b1);
-				DECODE_OUT_1 ("jump_forward %d", (int)b1);
+				DECODE_OUT_1 (stix, "jump_forward %zd", b1);
 				break;
 
 			case BCODE_JUMP_FORWARD_0:
 			case BCODE_JUMP_FORWARD_1:
 			case BCODE_JUMP_FORWARD_2:
 			case BCODE_JUMP_FORWARD_3:
-				DECODE_OUT_1 ("jump_forward %d", (int)(bcode & 0x3)); /* low 2 bits */
+				DECODE_OUT_1 (stix, "jump_forward %zd", (bcode & 0x3)); /* low 2 bits */
 				break;
 
 			case BCODE_JUMP_BACKWARD_X:
 				FETCH_PARAM_CODE_TO (stix, b1);
-				DECODE_OUT_1 ("jump_backward %d", (int)b1);
+				DECODE_OUT_1 (stix, "jump_backward %zd", b1);
 				stix->ip += b1;
 				break;
 
@@ -245,7 +249,7 @@ static int decode (stix_t* stix, stix_oop_method_t mth)
 			case BCODE_JUMP_BACKWARD_1:
 			case BCODE_JUMP_BACKWARD_2:
 			case BCODE_JUMP_BACKWARD_3:
-				DECODE_OUT_1 ("jump_backward %d", (int)(bcode & 0x3)); /* low 2 bits */
+				DECODE_OUT_1 (stix, "jump_backward %zd", (bcode & 0x3)); /* low 2 bits */
 				break;
 
 			case BCODE_JUMP_IF_TRUE_X:
@@ -258,18 +262,18 @@ static int decode (stix_t* stix, stix_oop_method_t mth)
 			case BCODE_JUMP_IF_FALSE_1:
 			case BCODE_JUMP_IF_FALSE_2:
 			case BCODE_JUMP_IF_FALSE_3:
-printf ("<<<<<<<<<<<<<< JUMP NOT IMPLEMENTED YET >>>>>>>>>>>> \n");
+DECODE_OUT_0 (stix, "<<<<<<<<<<<<<< JUMP NOT IMPLEMENTED YET >>>>>>>>>>>>");
 stix->errnum = STIX_ENOIMPL;
 return -1;
 
 			case BCODE_JUMP2_FORWARD:
 				FETCH_PARAM_CODE_TO (stix, b1);
-				DECODE_OUT_1 ("jump2_forward %d", (int)b1);
+				DECODE_OUT_1 (stix, "jump2_forward %zd", b1);
 				break;
 
 			case BCODE_JUMP2_BACKWARD:
 				FETCH_PARAM_CODE_TO (stix, b1);
-				DECODE_OUT_1 ("jump2_backward %d", (int)b1);
+				DECODE_OUT_1 (stix, "jump2_backward %zd", b1);
 				break;
 
 			/* -------------------------------------------------------- */
@@ -302,17 +306,17 @@ return -1;
 
 					if ((bcode >> 2) & 1)
 					{
-						DECODE_OUT_2 ("pop_into_ctxtempvar %d %d", (int)b1, (int)b2);
+						DECODE_OUT_2 (stix, "pop_into_ctxtempvar %zd %zd", b1, b2);
 					}
 					else
 					{
-						DECODE_OUT_2 ("store_into_ctxtempvar %d %d", (int)b1, (int)b2);
+						DECODE_OUT_2 (stix, "store_into_ctxtempvar %zd %zd", b1, b2);
 					}
 				}
 				else
 				{
 					/* push */
-					DECODE_OUT_2 ("push_ctxtempvar %d %d", (int)b1, (int)b2);
+					DECODE_OUT_2 (stix, "push_ctxtempvar %zd %zd", b1, b2);
 				}
 
 				break;
@@ -348,16 +352,16 @@ return -1;
 					/* store or pop */
 					if ((bcode >> 2) & 1)
 					{
-						DECODE_OUT_2 ("pop_into_objvar %d %d", (int)b1, (int)b2);
+						DECODE_OUT_2 (stix, "pop_into_objvar %zd %zd", b1, b2);
 					}
 					else
 					{
-						DECODE_OUT_2 ("store_into_objvar %d %d", (int)b1, (int)b2);
+						DECODE_OUT_2 (stix, "store_into_objvar %zd %zd", b1, b2);
 					}
 				}
 				else
 				{
-					DECODE_OUT_2 ("push_objvar %d %d", (int)b1, (int)b2);
+					DECODE_OUT_2 (stix, "push_objvar %zd %zd", b1, b2);
 				}
 
 				break;
@@ -383,77 +387,77 @@ return -1;
 				FETCH_BYTE_CODE_TO (stix, b2);
 
 			handle_send_message:
-				DECODE_OUT_3 ("send_message%s nargs=%d selector=%d", (((bcode >> 2) & 1)? "_to_super": ""), (int)b1, (int)b2);
+				DECODE_OUT_3 (stix, "send_message%hs %zd @%zd", (((bcode >> 2) & 1)? "_to_super": ""), b1, b2);
 				break; 
 
 			/* -------------------------------------------------------- */
 
 			case BCODE_PUSH_RECEIVER:
-				DECODE_OUT_0 ("push_receiver");
+				DECODE_OUT_0 (stix, "push_receiver");
 				break;
 
 			case BCODE_PUSH_NIL:
-				DECODE_OUT_0 ("push_nil");
+				DECODE_OUT_0 (stix, "push_nil");
 				break;
 
 			case BCODE_PUSH_TRUE:
-				DECODE_OUT_0 ("push_true");
+				DECODE_OUT_0 (stix, "push_true");
 				break;
 
 			case BCODE_PUSH_FALSE:
-				DECODE_OUT_0 ("push_false");
+				DECODE_OUT_0 (stix, "push_false");
 				break;
 
 			case BCODE_PUSH_CONTEXT:
-				DECODE_OUT_0 ("push_context");
+				DECODE_OUT_0 (stix, "push_context");
 				break;
 
 			case BCODE_PUSH_NEGONE:
-				DECODE_OUT_0 ("push_negone");
+				DECODE_OUT_0 (stix, "push_negone");
 				break;
 
 			case BCODE_PUSH_ZERO:
-				DECODE_OUT_0 ("push_zero");
+				DECODE_OUT_0 (stix, "push_zero");
 				break;
 
 			case BCODE_PUSH_ONE:
-				DECODE_OUT_0 ("push_one");
+				DECODE_OUT_0 (stix, "push_one");
 				break;
 
 			case BCODE_PUSH_TWO:
-				DECODE_OUT_0 ("push_two");
+				DECODE_OUT_0 (stix, "push_two");
 				break;
 
 			case BCODE_PUSH_INTLIT:
 				FETCH_PARAM_CODE_TO (stix, b1);
-				DECODE_OUT_1 ("push_intlit %d", (int)b1);
+				DECODE_OUT_1 (stix, "push_intlit %zd", b1);
 				break;
 
 			case BCODE_PUSH_NEGINTLIT:
 				FETCH_PARAM_CODE_TO (stix, b1);
-				DECODE_OUT_1 ("push_negintlit %d", (int)-b1);
+				DECODE_OUT_1 (stix, "push_negintlit %zd", -b1);
 				break;
 
 			/* -------------------------------------------------------- */
 
 			case BCODE_DUP_STACKTOP:
-				DECODE_OUT_0 ("dup_stacktop");
+				DECODE_OUT_0 (stix, "dup_stacktop");
 				break;
 
 			case BCODE_POP_STACKTOP:
-				DECODE_OUT_0 ("pop_stacktop");
+				DECODE_OUT_0 (stix, "pop_stacktop");
 				break;
 
 			case BCODE_RETURN_STACKTOP:
-				DECODE_OUT_0 ("return_stacktop");
+				DECODE_OUT_0 (stix, "return_stacktop");
 				break;
 
 			case BCODE_RETURN_RECEIVER:
-				DECODE_OUT_0 ("return_receiver");
+				DECODE_OUT_0 (stix, "return_receiver");
 				break;
 
 			case BCODE_RETURN_FROM_BLOCK:
-				DECODE_OUT_0 ("return_from_block");
+				DECODE_OUT_0 (stix, "return_from_block");
 				break;
 
 			case BCODE_MAKE_BLOCK:
@@ -462,7 +466,7 @@ return -1;
 				FETCH_PARAM_CODE_TO (stix, b1);
 				FETCH_PARAM_CODE_TO (stix, b2);
 
-				DECODE_OUT_2 ("make_block %d %d", (int)b1, (int)b2);
+				DECODE_OUT_2 (stix, "make_block %zd %zd", b1, b2);
 
 				STIX_ASSERT (b1 >= 0);
 				STIX_ASSERT (b2 >= b1);
@@ -470,16 +474,16 @@ return -1;
 			
 
 			case BCODE_SEND_BLOCK_COPY:
-				DECODE_OUT_0 ("send_block_copy");
+				DECODE_OUT_0 (stix, "send_block_copy");
 				break;
 
 			case BCODE_NOOP:
 				/* do nothing */
-				DECODE_OUT_0 ("noop");
+				DECODE_OUT_0 (stix, "noop");
 				break;
 
 			default:
-printf ("UNKNOWN BYTE CODE ENCOUNTERED %x\n", (int)bcode);
+				DECODE_OUT_1 (stix, "UNKNOWN BYTE CODE ENCOUNTERED %x", (int)bcode);
 				stix->errnum = STIX_EINTERN;
 				break;
 
@@ -489,15 +493,9 @@ printf ("UNKNOWN BYTE CODE ENCOUNTERED %x\n", (int)bcode);
 	/* print literal frame contents */
 	for (ip = 0; ip < STIX_OBJ_GET_SIZE(mth) - STIX_METHOD_NAMED_INSTVARS; ip++)
 	{
-		printf ("  %8lu ", (unsigned long int)ip);
-		print_object (stix, mth->slot[ip]);
-		printf ("\n");
+		DECODE_OUT_2 (stix, " @%-3lu %O", (unsigned long int)ip, mth->slot[ip]);
 	}
 
 	return 0;
 }
 
-int stix_decode (stix_t* stix, stix_oop_method_t mth)
-{
-	return decode (stix, mth);
-}
diff --git a/stix/lib/exec.c b/stix/lib/exec.c
index 1dcf554..01241c5 100644
--- a/stix/lib/exec.c
+++ b/stix/lib/exec.c
@@ -26,7 +26,6 @@
 
 #include "stix-prv.h"
 
-
 /* TODO: remove these headers after having migrated system-dependent functions of of this file */
 #if defined(_WIN32)
 #	include <windows.h>
@@ -1214,15 +1213,15 @@ static int prim_dump (stix_t* stix, stix_ooi_t nargs)
 
 	STIX_ASSERT (nargs >=  0);
 
-	printf ("RECEIVER: ");
+	stix_bfmtout (stix, "RECEIVER: ");
 	print_object (stix, STIX_STACK_GET(stix, stix->sp - nargs));
-	printf ("\n");
+	stix_bfmtout (stix, "\n");
 	for (i = nargs; i > 0; )
 	{
 		--i;
-		printf ("ARGUMENT: ");
+		stix_bfmtout (stix, "ARGUMENT: ");
 		print_object (stix, STIX_STACK_GET(stix, stix->sp - i));
-		printf ("\n");
+		stix_bfmtout (stix, "\n");
 	}
 
 	STIX_STACK_POPS (stix, nargs);
@@ -2667,7 +2666,7 @@ typedef struct prim_t prim_t;
 
 static prim_t primitives[] =
 {
-	{   0, MAX_NARGS,  prim_dump,                 "_dump"                },
+	{   0, MAX_NARGS,  prim_dump,          "_dump"                },
 
 	{   1,  1,  prim_identical,            "_identical"           },
 	{   1,  1,  prim_not_identical,        "_not_identical"       },
diff --git a/stix/lib/fmt.c b/stix/lib/fmt.c
new file mode 100644
index 0000000..3c227a6
--- /dev/null
+++ b/stix/lib/fmt.c
@@ -0,0 +1,252 @@
+/*
+ * $Id$
+ *
+    Copyright (c) 2014-2016 Chung, Hyung-Hwan. All rights reserved.
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions
+    are met:
+    1. Redistributions of source code must retain the above copyright
+       notice, this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright
+       notice, this list of conditions and the following disclaimer in the
+       documentation and/or other materials provided with the distribution.
+
+    THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR
+    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+    OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+    IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+    NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+    THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "stix-prv.h"
+
+#include <stdio.h> /* for snrintf(). used for floating-point number formatting */
+#include <stdarg.h>
+
+#if defined(_MSC_VER) || defined(__BORLANDC__) || (defined(__WATCOMC__) && (__WATCOMC__ < 1200))
+#	define snprintf _snprintf 
+#	if !defined(HAVE_SNPRINTF)
+#		define HAVE_SNPRINTF
+#	endif
+#endif
+#if defined(HAVE_QUADMATH_H)
+#	include <quadmath.h> /* for quadmath_snprintf() */
+#endif
+/* TODO: remove stdio.h and quadmath.h once snprintf gets replaced by own 
+floting-point conversion implementation*/
+
+/* Max number conversion buffer length: 
+ * stix_intmax_t in base 2, plus NUL byte. */
+#define MAXNBUF (STIX_SIZEOF(stix_intmax_t) * 8 + 1)
+
+enum
+{
+	/* integer */
+	LF_C = (1 << 0),
+	LF_H = (1 << 1),
+	LF_J = (1 << 2),
+	LF_L = (1 << 3),
+	LF_Q = (1 << 4),
+	LF_T = (1 << 5),
+	LF_Z = (1 << 6),
+
+	/* long double */
+	LF_LD = (1 << 7),
+	/* __float128 */
+	LF_QD = (1 << 8)
+};
+
+static struct
+{
+	stix_uint8_t flag; /* for single occurrence */
+	stix_uint8_t dflag; /* for double occurrence */
+} lm_tab[26] = 
+{
+	{ 0,    0 }, /* a */
+	{ 0,    0 }, /* b */
+	{ 0,    0 }, /* c */
+	{ 0,    0 }, /* d */
+	{ 0,    0 }, /* e */
+	{ 0,    0 }, /* f */
+	{ 0,    0 }, /* g */
+	{ LF_H, LF_C }, /* h */
+	{ 0,    0 }, /* i */
+	{ LF_J, 0 }, /* j */
+	{ 0,    0 }, /* k */
+	{ LF_L, LF_Q }, /* l */
+	{ 0,    0 }, /* m */
+	{ 0,    0 }, /* n */
+	{ 0,    0 }, /* o */
+	{ 0,    0 }, /* p */
+	{ LF_Q, 0 }, /* q */
+	{ 0,    0 }, /* r */
+	{ 0,    0 }, /* s */
+	{ LF_T, 0 }, /* t */
+	{ 0,    0 }, /* u */
+	{ 0,    0 }, /* v */
+	{ 0,    0 }, /* w */
+	{ 0,    0 }, /* z */
+	{ 0,    0 }, /* y */
+	{ LF_Z, 0 }, /* z */
+};
+
+
+enum 
+{
+	FLAGC_DOT       = (1 << 0),
+	FLAGC_SPACE     = (1 << 1),
+	FLAGC_SHARP     = (1 << 2),
+	FLAGC_SIGN      = (1 << 3),
+	FLAGC_LEFTADJ   = (1 << 4),
+	FLAGC_ZEROPAD   = (1 << 5),
+	FLAGC_WIDTH     = (1 << 6),
+	FLAGC_PRECISION = (1 << 7),
+	FLAGC_STAR1     = (1 << 8),
+	FLAGC_STAR2     = (1 << 9),
+	FLAGC_LENMOD    = (1 << 10) /* length modifier */
+};
+
+static const stix_bch_t hex2ascii_lower[] = 
+{
+	'0','1','2','3','4','5','6','7','8','9',
+	'a','b','c','d','e','f','g','h','i','j','k','l','m',
+	'n','o','p','q','r','s','t','u','v','w','x','y','z'
+};
+
+static const stix_bch_t hex2ascii_upper[] = 
+{
+	'0','1','2','3','4','5','6','7','8','9',
+	'A','B','C','D','E','F','G','H','I','J','K','L','M',
+	'N','O','P','Q','R','S','T','U','V','W','X','H','Z'
+};
+
+static stix_ooch_t ooch_nullstr[] = { '(','n','u','l','l', ')','\0' };
+static stix_bch_t bch_nullstr[] = { '(','n','u','l','l', ')','\0' };
+
+typedef int (*stix_fmtout_put_t) (
+	stix_t*     stix,
+	stix_ooch_t c
+);
+
+typedef struct stix_fmtout_t stix_fmtout_t;
+struct stix_fmtout_t
+{
+	stix_oow_t         count; /* out */
+	stix_oow_t         limit; /* in */
+	stix_fmtout_put_t  put;
+};
+
+/* ------------------------------------------------------------------------- */
+/*
+ * Put a NUL-terminated ASCII number (base <= 36) in a buffer in reverse
+ * order; return an optional length and a pointer to the last character
+ * written in the buffer (i.e., the first character of the string).
+ * The buffer pointed to by `nbuf' must have length >= MAXNBUF.
+ */
+
+static stix_bch_t* sprintn_lower (stix_bch_t* nbuf, stix_uintmax_t num, int base, stix_ooi_t *lenp)
+{
+	stix_bch_t* p;
+
+	p = nbuf;
+	*p = '\0';
+	do { *++p = hex2ascii_lower[num % base]; } while (num /= base);
+
+	if (lenp) *lenp = p - nbuf;
+	return p; /* returns the end */
+}
+
+static stix_bch_t* sprintn_upper (stix_bch_t* nbuf, stix_uintmax_t num, int base, stix_ooi_t *lenp)
+{
+	stix_bch_t* p;
+
+	p = nbuf;
+	*p = '\0';
+	do { *++p = hex2ascii_upper[num % base]; } while (num /= base);
+
+	if (lenp) *lenp = p - nbuf;
+	return p; /* returns the end */
+}
+
+/* ------------------------------------------------------------------------- */
+
+static int put_ooch (stix_t* stix, stix_ooch_t ch)
+{
+
+	if (stix->log.len >= stix->log.capa)
+	{
+		stix_oow_t newcapa;
+		stix_ooch_t* tmp;
+
+		newcapa = stix->log.capa + 512; /* TODO: adjust this capacity */
+		tmp = stix_reallocmem (stix, stix->log.ptr, newcapa * STIX_SIZEOF(*tmp));
+		if (!tmp) return -1;
+
+		stix->log.ptr = tmp;
+		stix->log.capa = newcapa;
+	}
+
+	stix->log.ptr[stix->log.len++] = ch;
+	if (ch == '\n')
+	{
+		stix->vmprim.log_write (stix, 0, stix->log.ptr, stix->log.len);
+/* TODO: error handling */
+		stix->log.len = 0;
+	}
+
+	return 1;
+}
+
+/* ------------------------------------------------------------------------- */
+
+#undef fmtchar_t
+#undef fmtoutv
+#define fmtchar_t stix_bch_t
+#define fmtoutv stix_bfmtoutv
+#include "fmtoutv.h"
+
+#undef fmtchar_t
+#undef fmtoutv
+#define fmtchar_t stix_ooch_t
+#define fmtoutv stix_oofmtoutv
+#include "fmtoutv.h"
+
+stix_ooi_t stix_bfmtout (stix_t* stix, const stix_bch_t* fmt, ...)
+{
+	stix_ooi_t x;
+	va_list ap;
+	stix_fmtout_t fo;
+
+	fo.count = 0;
+	fo.limit = STIX_TYPE_MAX(stix_ooi_t);
+	fo.put = put_ooch;
+
+	va_start (ap, fmt);
+	x = stix_bfmtoutv (stix, fmt, &fo, ap);
+	va_end (ap);
+
+	return (x <= -1)? -1: fo.count;
+}
+
+stix_ooi_t stix_oofmtout (stix_t* stix, const stix_ooch_t* fmt, ...)
+{
+	stix_ooi_t x;
+	va_list ap;
+	stix_fmtout_t fo;
+
+	fo.count = 0;
+	fo.limit = STIX_TYPE_MAX(stix_ooi_t);
+	fo.put = put_ooch;
+
+	va_start (ap, fmt);
+	x = stix_oofmtoutv (stix, fmt, &fo, ap);
+	va_end (ap);
+
+	return (x <= -1)? -1: fo.count;
+}
diff --git a/stix/lib/fmtoutv.h b/stix/lib/fmtoutv.h
new file mode 100644
index 0000000..5dacf9a
--- /dev/null
+++ b/stix/lib/fmtoutv.h
@@ -0,0 +1,900 @@
+/*
+ * $Id$
+ *
+    Copyright (c) 2014-2016 Chung, Hyung-Hwan. All rights reserved.
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions
+    are met:
+    1. Redistributions of source code must retain the above copyright
+       notice, this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright
+       notice, this list of conditions and the following disclaimer in the
+       documentation and/or other materials provided with the distribution.
+
+    THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR
+    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+    OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+    IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+    NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+    THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/*
+ * This file contains a formatted output routine derived from kvprintf() 
+ * of FreeBSD. It has been heavily modified and bug-fixed.
+ */
+
+/*
+ * Copyright (c) 1986, 1988, 1991, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ * (c) UNIX System Laboratories, Inc.
+ * All or some portions of this file are derived from material licensed
+ * to the University of California by American Telephone and Telegraph
+ * Co. or Unix System Laboratories, Inc. and are reproduced herein with
+ * the permission of UNIX System Laboratories, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ */
+
+
+/* NOTE: data output is aborted if the data limit is reached or 
+ *       I/O error occurs  */
+
+#undef PUT_CHAR
+
+#define PUT_CHAR(stix,c) do { \
+	int xx; \
+	if (data->count >= data->limit) goto done; \
+	if ((xx = data->put (stix, c)) <= -1) goto oops; \
+	if (xx == 0) goto done; \
+	data->count++; \
+} while (0)
+
+int fmtoutv (stix_t* stix, const fmtchar_t* fmt, stix_fmtout_t* data, va_list ap)
+{
+	const fmtchar_t* percent;
+	stix_bch_t nbuf[MAXNBUF], bch;
+	const stix_bch_t* nbufp;
+	int n, base, neg, sign;
+	stix_ooi_t tmp, width, precision;
+	stix_ooch_t ch, padc;
+	int lm_flag, lm_dflag, flagc, numlen;
+	stix_uintmax_t num = 0;
+	int stop = 0;
+
+#if 0
+	stix_bchbuf_t* fltfmt;
+	stix_oochbuf_t* fltout;
+#endif
+	stix_bch_t* (*sprintn) (stix_bch_t* nbuf, stix_uintmax_t num, int base, stix_ooi_t* lenp);
+
+	data->count = 0;
+
+#if 0
+	fltfmt = &stix->d->fltfmt;
+	fltout = &stix->d->fltout;
+
+	fltfmt->ptr  = fltfmt->sbuf;
+	fltfmt->capa = STIX_COUNTOF(fltfmt->sbuf) - 1;
+
+	fltout->ptr  = fltout->sbuf;
+	fltout->capa = STIX_COUNTOF(fltout->sbuf) - 1;
+#endif
+
+	while (1)
+	{
+		while ((ch = *fmt++) != '%' || stop) 
+		{
+			if (ch == '\0') goto done;
+			PUT_CHAR (stix, ch);
+		}
+		percent = fmt - 1;
+
+		padc = ' '; 
+		width = 0; precision = 0;
+		neg = 0; sign = 0;
+
+		lm_flag = 0; lm_dflag = 0; flagc = 0; 
+		sprintn = sprintn_lower;
+
+reswitch:
+		switch (ch = *fmt++) 
+		{
+		case '%': /* %% */
+			bch = ch;
+			goto print_lowercase_c;
+
+		/* flag characters */
+		case '.':
+			if (flagc & FLAGC_DOT) goto invalid_format;
+			flagc |= FLAGC_DOT;
+			goto reswitch;
+
+		case '#': 
+			if (flagc & (FLAGC_WIDTH | FLAGC_DOT | FLAGC_LENMOD)) goto invalid_format;
+			flagc |= FLAGC_SHARP;
+			goto reswitch;
+
+		case ' ':
+			if (flagc & (FLAGC_WIDTH | FLAGC_DOT | FLAGC_LENMOD)) goto invalid_format;
+			flagc |= FLAGC_SPACE;
+			goto reswitch;
+
+		case '+': /* place sign for signed conversion */
+			if (flagc & (FLAGC_WIDTH | FLAGC_DOT | FLAGC_LENMOD)) goto invalid_format;
+			flagc |= FLAGC_SIGN;
+			goto reswitch;
+
+		case '-': /* left adjusted */
+			if (flagc & (FLAGC_WIDTH | FLAGC_DOT | FLAGC_LENMOD)) goto invalid_format;
+			if (flagc & FLAGC_DOT)
+			{
+				goto invalid_format;
+			}
+			else
+			{
+				flagc |= FLAGC_LEFTADJ;
+				if (flagc & FLAGC_ZEROPAD)
+				{
+					padc = ' ';
+					flagc &= ~FLAGC_ZEROPAD;
+				}
+			}
+			
+			goto reswitch;
+
+		case '*': /* take the length from the parameter */
+			if (flagc & FLAGC_DOT) 
+			{
+				if (flagc & (FLAGC_STAR2 | FLAGC_PRECISION)) goto invalid_format;
+				flagc |= FLAGC_STAR2;
+
+				precision = va_arg(ap, stix_ooi_t); /* this deviates from the standard printf that accepts 'int' */
+				if (precision < 0) 
+				{
+					/* if precision is less than 0, 
+					 * treat it as if no .precision is specified */
+					flagc &= ~FLAGC_DOT;
+					precision = 0;
+				}
+			} 
+			else 
+			{
+				if (flagc & (FLAGC_STAR1 | FLAGC_WIDTH)) goto invalid_format;
+				flagc |= FLAGC_STAR1;
+
+				width = va_arg(ap, stix_ooi_t); /* it deviates from the standard printf that accepts 'int' */
+				if (width < 0) 
+				{
+					/*
+					if (flagc & FLAGC_LEFTADJ) 
+						flagc  &= ~FLAGC_LEFTADJ;
+					else
+					*/
+						flagc |= FLAGC_LEFTADJ;
+					width = -width;
+				}
+			}
+			goto reswitch;
+
+		case '0': /* zero pad */
+			if (flagc & FLAGC_LENMOD) goto invalid_format;
+			if (!(flagc & (FLAGC_DOT | FLAGC_LEFTADJ)))
+			{
+				padc = '0';
+				flagc |= FLAGC_ZEROPAD;
+				goto reswitch;
+			}
+		/* end of flags characters */
+
+		case '1': case '2': case '3': case '4':
+		case '5': case '6': case '7': case '8': case '9':
+			for (n = 0;; ++fmt) 
+			{
+				n = n * 10 + ch - '0';
+				ch = *fmt;
+				if (ch < '0' || ch > '9') break;
+			}
+			if (flagc & FLAGC_DOT) 
+			{
+				if (flagc & FLAGC_STAR2) goto invalid_format;
+				precision = n;
+				flagc |= FLAGC_PRECISION;
+			}
+			else 
+			{
+				if (flagc & FLAGC_STAR1) goto invalid_format;
+				width = n;
+				flagc |= FLAGC_WIDTH;
+			}
+			goto reswitch;
+
+		/* length modifiers */
+		case 'h': /* short int */
+		case 'l': /* long int */
+		case 'q': /* long long int */
+		case 'j': /* uintmax_t */
+		case 'z': /* size_t */
+		case 't': /* ptrdiff_t */
+			if (lm_flag & (LF_LD | LF_QD)) goto invalid_format;
+
+			flagc |= FLAGC_LENMOD;
+			if (lm_dflag)
+			{
+				/* error */
+				goto invalid_format;
+			}
+			else if (lm_flag)
+			{
+				if (lm_tab[ch - 'a'].dflag && lm_flag == lm_tab[ch - 'a'].flag)
+				{
+					lm_flag &= ~lm_tab[ch - 'a'].flag;
+					lm_flag |= lm_tab[ch - 'a'].dflag;
+					lm_dflag |= lm_flag;
+					goto reswitch;
+				}
+				else
+				{
+					/* error */
+					goto invalid_format;
+				}
+			}
+			else 
+			{
+				lm_flag |= lm_tab[ch - 'a'].flag;
+				goto reswitch;
+			}
+			break;
+
+		case 'L': /* long double */
+			if (flagc & FLAGC_LENMOD) 
+			{
+				/* conflict with other length modifier */
+				goto invalid_format; 
+			}
+			flagc |= FLAGC_LENMOD;
+			lm_flag |= LF_LD;
+			goto reswitch;
+
+		case 'Q': /* __float128 */
+			if (flagc & FLAGC_LENMOD)
+			{
+				/* conflict with other length modifier */
+				goto invalid_format; 
+			}
+			flagc |= FLAGC_LENMOD;
+			lm_flag |= LF_QD;
+			goto reswitch;
+			
+		/* end of length modifiers */
+
+		case 'n':
+			if (lm_flag & LF_J) /* j */
+				*(va_arg(ap, stix_intmax_t*)) = data->count;
+			else if (lm_flag & LF_Z) /* z */
+				*(va_arg(ap, stix_ooi_t*)) = data->count;
+		#if (STIX_SIZEOF_LONG_LONG > 0)
+			else if (lm_flag & LF_Q) /* ll */
+				*(va_arg(ap, long long int*)) = data->count;
+		#endif
+			else if (lm_flag & LF_L) /* l */
+				*(va_arg(ap, long int*)) = data->count;
+			else if (lm_flag & LF_H) /* h */
+				*(va_arg(ap, short int*)) = data->count;
+			else if (lm_flag & LF_C) /* hh */
+				*(va_arg(ap, char*)) = data->count;
+			else if (flagc & FLAGC_LENMOD)
+			{
+				stix->errnum = STIX_EINVAL;
+				goto oops;
+			}
+			else
+				*(va_arg(ap, int*)) = data->count;
+			break;
+ 
+		/* signed integer conversions */
+		case 'd':
+		case 'i': /* signed conversion */
+			base = 10;
+			sign = 1;
+			goto handle_sign;
+		/* end of signed integer conversions */
+
+		/* unsigned integer conversions */
+		case 'o': 
+			base = 8;
+			goto handle_nosign;
+		case 'u':
+			base = 10;
+			goto handle_nosign;
+		case 'X':
+			sprintn = sprintn_upper;
+		case 'x':
+			base = 16;
+			goto handle_nosign;
+		/* end of unsigned integer conversions */
+
+		case 'p': /* pointer */
+			base = 16;
+
+			if (width == 0) flagc |= FLAGC_SHARP;
+			else flagc &= ~FLAGC_SHARP;
+
+			num = (stix_uintptr_t)va_arg(ap, void*);
+			goto number;
+
+		case 'c':
+		{
+			/* zeropad must not take effect for 'c' */
+			if (flagc & FLAGC_ZEROPAD) padc = ' '; 
+			if (lm_flag & LF_L) goto uppercase_c;
+
+		lowercase_c:
+			bch = STIX_SIZEOF(stix_bch_t) < STIX_SIZEOF(int)? va_arg(ap, int): va_arg(ap, stix_bch_t);
+
+		print_lowercase_c:
+			/* precision 0 doesn't kill the letter */
+			width--;
+			if (!(flagc & FLAGC_LEFTADJ) && width > 0)
+			{
+				while (width--) PUT_CHAR (stix, padc);
+			}
+			PUT_CHAR (stix, bch);
+			if ((flagc & FLAGC_LEFTADJ) && width > 0)
+			{
+				while (width--) PUT_CHAR (stix, padc);
+			}
+			break;
+		}
+
+		case 'C':
+		{
+			stix_ooch_t ooch;
+
+			/* zeropad must not take effect for 'C' */
+			if (flagc & FLAGC_ZEROPAD) padc = ' ';
+			if (lm_flag & LF_H) goto lowercase_c;
+		uppercase_c:
+			ooch = STIX_SIZEOF(stix_ooch_t) < STIX_SIZEOF(int)? va_arg(ap, int): va_arg(ap, stix_ooch_t);
+
+			/* precision 0 doesn't kill the letter */
+			width--;
+			if (!(flagc & FLAGC_LEFTADJ) && width > 0)
+			{
+				while (width--) PUT_CHAR (stix, padc);
+			}
+
+			PUT_CHAR (stix, ooch);
+
+			if ((flagc & FLAGC_LEFTADJ) && width > 0)
+			{
+				while (width--) PUT_CHAR (stix, padc);
+			}
+			break;
+		}
+
+		case 's':
+		{
+			const stix_bch_t* bsp;
+			stix_oow_t bslen, slen;
+
+			/* zeropad must not take effect for 'S' */
+			if (flagc & FLAGC_ZEROPAD) padc = ' ';
+			if (lm_flag & LF_H) goto lowercase_s;
+		lowercase_s:
+
+			bsp = va_arg (ap, stix_bch_t*);
+			if (bsp == STIX_NULL) bsp = bch_nullstr;
+
+			/* get the length */
+			for (bslen = 0; bsp[bslen]; bslen++);
+
+			if (stix_utf8toucs (bsp, &bslen, STIX_NULL, &slen) <= -1)
+			{ 
+				/* conversion error */
+				stix->errnum = STIX_EECERR;
+				goto oops;
+			}
+
+			/* slen holds 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 (stix, padc);
+			}
+
+			{
+				stix_ooch_t conv_buf[32]; 
+				stix_oow_t i, conv_len, src_len, tot_len = 0;
+				while (n > 0)
+				{
+					STIX_ASSERT (bslen > tot_len);
+
+					src_len = bslen - tot_len;
+					conv_len = STIX_COUNTOF(conv_buf);
+
+					/* this must not fail since the dry-run above was successful */
+					stix_utf8toucs (&bsp[tot_len], &src_len, conv_buf, &conv_len);
+					tot_len += src_len;
+
+					if (conv_len > n) conv_len = n;
+					for (i = 0; i < conv_len; i++)
+					{
+						PUT_CHAR (stix, conv_buf[i]);
+					}
+
+					n -= conv_len;
+				}
+			}
+			
+			if ((flagc & FLAGC_LEFTADJ) && width > 0)
+			{
+				while (width--) PUT_CHAR (stix, padc);
+			}
+			break;
+		}
+
+		case 'S':
+		{
+			const stix_ooch_t* sp;
+
+			/* zeropad must not take effect for 's' */
+			if (flagc & FLAGC_ZEROPAD) padc = ' ';
+			if (lm_flag & LF_L) goto uppercase_s;
+		uppercase_s:
+			sp = va_arg (ap, stix_ooch_t*);
+			if (sp == STIX_NULL) sp = ooch_nullstr;
+
+			if (flagc & FLAGC_DOT)
+			{
+				for (n = 0; n < precision && sp[n]; n++);
+			}
+			else
+			{
+				for (n = 0; sp[n]; n++);
+			}
+
+			width -= n;
+
+			if (!(flagc & FLAGC_LEFTADJ) && width > 0)
+			{
+				while (width--) PUT_CHAR (stix, padc);
+			}
+			while (n--) PUT_CHAR (stix, *sp++);
+			if ((flagc & FLAGC_LEFTADJ) && width > 0)
+			{
+				while (width--) PUT_CHAR (stix, padc);
+			}
+			break;
+		}
+
+		case 'O': /* object - ignore precision, width, adjustment */
+			print_object (stix, va_arg (ap, stix_oop_t));
+			break;
+
+#if 0
+		case 'e':
+		case 'E':
+		case 'f':
+		case 'F':
+		case 'g':
+		case 'G':
+		/*
+		case 'a':
+		case 'A':
+		*/
+		{
+			/* let me rely on snprintf until i implement float-point to string conversion */
+			int q;
+			stix_oow_t fmtlen;
+		#if (STIX_SIZEOF___FLOAT128 > 0) && defined(HAVE_QUADMATH_SNPRINTF)
+			__float128 v_qd;
+		#endif
+			long double v_ld;
+			double v_d;
+			int dtype = 0;
+			stix_oow_t newcapa;
+
+			if (lm_flag & LF_J)
+			{
+			#if (STIX_SIZEOF___FLOAT128 > 0) && defined(HAVE_QUADMATH_SNPRINTF) && (STIX_SIZEOF_FLTMAX_T == STIX_SIZEOF___FLOAT128)
+				v_qd = va_arg (ap, stix_fltmax_t);
+				dtype = LF_QD;
+			#elif STIX_SIZEOF_FLTMAX_T == STIX_SIZEOF_DOUBLE
+				v_d = va_arg (ap, stix_fltmax_t);
+			#elif STIX_SIZEOF_FLTMAX_T == STIX_SIZEOF_LONG_DOUBLE
+				v_ld = va_arg (ap, stix_fltmax_t);
+				dtype = LF_LD;
+			#else
+				#error Unsupported stix_flt_t
+			#endif
+			}
+			else if (lm_flag & LF_Z)
+			{
+				/* stix_flt_t is limited to double or long double */
+
+				/* precedence goes to double if sizeof(double) == sizeof(long double) 
+				 * for example, %Lf didn't work on some old platforms.
+				 * so i prefer the format specifier with no modifier.
+				 */
+			#if STIX_SIZEOF_FLT_T == STIX_SIZEOF_DOUBLE
+				v_d = va_arg (ap, stix_flt_t);
+			#elif STIX_SIZEOF_FLT_T == STIX_SIZEOF_LONG_DOUBLE
+				v_ld = va_arg (ap, stix_flt_t);
+				dtype = LF_LD;
+			#else
+				#error Unsupported stix_flt_t
+			#endif
+			}
+			else if (lm_flag & (LF_LD | LF_L))
+			{
+				v_ld = va_arg (ap, long double);
+				dtype = LF_LD;
+			}
+		#if (STIX_SIZEOF___FLOAT128 > 0) && defined(HAVE_QUADMATH_SNPRINTF)
+			else if (lm_flag & (LF_QD | LF_Q))
+			{
+				v_qd = va_arg (ap, __float128);
+				dtype = LF_QD;
+			}
+		#endif
+			else if (flagc & FLAGC_LENMOD)
+			{
+				stix->errnum = STIX_EINVAL;
+				goto oops;
+			}
+			else
+			{
+				v_d = va_arg (ap, double);
+			}
+
+			fmtlen = fmt - percent;
+			if (fmtlen > fltfmt->capa)
+			{
+				if (fltfmt->ptr == fltfmt->sbuf)
+				{
+					fltfmt->ptr = STIX_MMGR_ALLOC (STIX_MMGR_GETDFL(), STIX_SIZEOF(*fltfmt->ptr) * (fmtlen + 1));
+					if (fltfmt->ptr == STIX_NULL) goto oops;
+				}
+				else
+				{
+					stix_mchar_t* tmpptr;
+
+					tmpptr = STIX_MMGR_REALLOC (STIX_MMGR_GETDFL(), fltfmt->ptr, STIX_SIZEOF(*fltfmt->ptr) * (fmtlen + 1));
+					if (tmpptr == STIX_NULL) goto oops;
+					fltfmt->ptr = tmpptr;
+				}
+
+				fltfmt->capa = fmtlen;
+			}
+
+			/* compose back the format specifier */
+			fmtlen = 0;
+			fltfmt->ptr[fmtlen++] = '%';
+			if (flagc & FLAGC_SPACE) fltfmt->ptr[fmtlen++] = ' ';
+			if (flagc & FLAGC_SHARP) fltfmt->ptr[fmtlen++] = '#';
+			if (flagc & FLAGC_SIGN) fltfmt->ptr[fmtlen++] = '+';
+			if (flagc & FLAGC_LEFTADJ) fltfmt->ptr[fmtlen++] = '-';
+			if (flagc & FLAGC_ZEROPAD) fltfmt->ptr[fmtlen++] = '0';
+
+			if (flagc & FLAGC_STAR1) fltfmt->ptr[fmtlen++] = '*';
+			else if (flagc & FLAGC_WIDTH) 
+			{
+				fmtlen += stix_fmtuintmaxtombs (
+					&fltfmt->ptr[fmtlen], fltfmt->capa - fmtlen, 
+					width, 10, -1, '\0', STIX_NULL);
+			}
+			if (flagc & FLAGC_DOT) fltfmt->ptr[fmtlen++] = '.';
+			if (flagc & FLAGC_STAR2) fltfmt->ptr[fmtlen++] = '*';
+			else if (flagc & FLAGC_PRECISION) 
+			{
+				fmtlen += stix_fmtuintmaxtombs (
+					&fltfmt->ptr[fmtlen], fltfmt->capa - fmtlen, 
+					precision, 10, -1, '\0', STIX_NULL);
+			}
+
+			if (dtype == LF_LD)
+				fltfmt->ptr[fmtlen++] = 'L';
+		#if (STIX_SIZEOF___FLOAT128 > 0)
+			else if (dtype == LF_QD)
+				fltfmt->ptr[fmtlen++] = 'Q';
+		#endif
+
+			fltfmt->ptr[fmtlen++] = ch;
+			fltfmt->ptr[fmtlen] = '\0';
+
+		#if defined(HAVE_SNPRINTF)
+			/* nothing special here */
+		#else
+			/* best effort to avoid buffer overflow when no snprintf is available. 
+			 * i really can't do much if it happens. */
+			newcapa = precision + width + 32;
+			if (fltout->capa < newcapa)
+			{
+				STIX_ASSERT (fltout->ptr == fltout->sbuf);
+
+				fltout->ptr = STIX_MMGR_ALLOC (STIX_MMGR_GETDFL(), STIX_SIZEOF(char_t) * (newcapa + 1));
+				if (fltout->ptr == STIX_NULL) goto oops;
+				fltout->capa = newcapa;
+			}
+		#endif
+
+			while (1)
+			{
+
+				if (dtype == LF_LD)
+				{
+				#if defined(HAVE_SNPRINTF)
+					q = snprintf ((stix_mchar_t*)fltout->ptr, fltout->capa + 1, fltfmt->ptr, v_ld);
+				#else
+					q = sprintf ((stix_mchar_t*)fltout->ptr, fltfmt->ptr, v_ld);
+				#endif
+				}
+			#if (STIX_SIZEOF___FLOAT128 > 0) && defined(HAVE_QUADMATH_SNPRINTF)
+				else if (dtype == LF_QD)
+				{
+					q = quadmath_snprintf ((stix_mchar_t*)fltout->ptr, fltout->capa + 1, fltfmt->ptr, v_qd);
+				}
+			#endif
+				else
+				{
+				#if defined(HAVE_SNPRINTF)
+					q = snprintf ((stix_mchar_t*)fltout->ptr, fltout->capa + 1, fltfmt->ptr, v_d);
+				#else
+					q = sprintf ((stix_mchar_t*)fltout->ptr, fltfmt->ptr, v_d);
+				#endif
+				}
+				if (q <= -1) goto oops;
+				if (q <= fltout->capa) break;
+
+				newcapa = fltout->capa * 2;
+				if (newcapa < q) newcapa = q;
+
+				if (fltout->ptr == fltout->sbuf)
+				{
+					fltout->ptr = STIX_MMGR_ALLOC (STIX_MMGR_GETDFL(), STIX_SIZEOF(char_t) * (newcapa + 1));
+					if (fltout->ptr == STIX_NULL) goto oops;
+				}
+				else
+				{
+					char_t* tmpptr;
+
+					tmpptr = STIX_MMGR_REALLOC (STIX_MMGR_GETDFL(), fltout->ptr, STIX_SIZEOF(char_t) * (newcapa + 1));
+					if (tmpptr == STIX_NULL) goto oops;
+					fltout->ptr = tmpptr;
+				}
+				fltout->capa = newcapa;
+			}
+
+			if (STIX_SIZEOF(char_t) != STIX_SIZEOF(stix_mchar_t))
+			{
+				fltout->ptr[q] = '\0';
+				while (q > 0)
+				{
+					q--;
+					fltout->ptr[q] = ((stix_mchar_t*)fltout->ptr)[q];
+				}
+			}
+
+			sp = fltout->ptr;
+			flagc &= ~FLAGC_DOT;
+			width = 0;
+			precision = 0;
+			goto print_lowercase_s;
+		}
+#endif
+
+
+handle_nosign:
+			sign = 0;
+			if (lm_flag & LF_J)
+			{
+			#if defined(__GNUC__) && \
+			    (STIX_SIZEOF_UINTMAX_T > STIX_SIZEOF_OOW_T) && \
+			    (STIX_SIZEOF_UINTMAX_T != STIX_SIZEOF_LONG_LONG) && \
+			    (STIX_SIZEOF_UINTMAX_T != STIX_SIZEOF_LONG)
+				/* GCC-compiled binaries crashed when getting stix_uintmax_t with va_arg.
+				 * This is just a work-around for it */
+				int i;
+				for (i = 0, num = 0; i < STIX_SIZEOF(stix_uintmax_t) / STIX_SIZEOF(stix_oow_t); i++)
+				{	
+				#if defined(STIX_ENDIAN_BIG)
+					num = num << (8 * STIX_SIZEOF(stix_oow_t)) | (va_arg (ap, stix_oow_t));
+				#else
+					register int shift = i * STIX_SIZEOF(stix_oow_t);
+					stix_oow_t x = va_arg (ap, stix_oow_t);
+					num |= (stix_uintmax_t)x << (shift * 8);
+				#endif
+				}
+			#else
+				num = va_arg (ap, stix_uintmax_t);
+			#endif
+			}
+#if 0
+			else if (lm_flag & LF_T)
+				num = va_arg (ap, stix_ptrdiff_t);
+#endif
+			else if (lm_flag & LF_Z)
+				num = va_arg (ap, stix_oow_t);
+			#if (STIX_SIZEOF_LONG_LONG > 0)
+			else if (lm_flag & LF_Q)
+				num = va_arg (ap, unsigned long long int);
+			#endif
+			else if (lm_flag & (LF_L | LF_LD))
+				num = va_arg (ap, unsigned long int);
+			else if (lm_flag & LF_H)
+				num = (unsigned short int)va_arg (ap, int);
+			else if (lm_flag & LF_C)
+				num = (unsigned char)va_arg (ap, int);
+			else
+				num = va_arg (ap, unsigned int);
+			goto number;
+
+handle_sign:
+			if (lm_flag & LF_J)
+			{
+			#if defined(__GNUC__) && \
+			    (STIX_SIZEOF_INTMAX_T > STIX_SIZEOF_OOI_T) && \
+			    (STIX_SIZEOF_UINTMAX_T != STIX_SIZEOF_LONG_LONG) && \
+			    (STIX_SIZEOF_UINTMAX_T != STIX_SIZEOF_LONG)
+				/* GCC-compiled binraries crashed when getting stix_uintmax_t with va_arg.
+				 * This is just a work-around for it */
+				int i;
+				for (i = 0, num = 0; i < STIX_SIZEOF(stix_intmax_t) / STIX_SIZEOF(stix_oow_t); i++)
+				{
+				#if defined(STIX_ENDIAN_BIG)
+					num = num << (8 * STIX_SIZEOF(stix_oow_t)) | (va_arg (ap, stix_oow_t));
+				#else
+					register int shift = i * STIX_SIZEOF(stix_oow_t);
+					stix_oow_t x = va_arg (ap, stix_oow_t);
+					num |= (stix_uintmax_t)x << (shift * 8);
+				#endif
+				}
+			#else
+				num = va_arg (ap, stix_intmax_t);
+			#endif
+			}
+
+#if 0
+			else if (lm_flag & LF_T)
+				num = va_arg(ap, stix_ptrdiff_t);
+#endif
+			else if (lm_flag & LF_Z)
+				num = va_arg (ap, stix_ooi_t);
+			#if (STIX_SIZEOF_LONG_LONG > 0)
+			else if (lm_flag & LF_Q)
+				num = va_arg (ap, long long int);
+			#endif
+			else if (lm_flag & (LF_L | LF_LD))
+				num = va_arg (ap, long int);
+			else if (lm_flag & LF_H)
+				num = (short int)va_arg (ap, int);
+			else if (lm_flag & LF_C)
+				num = (char)va_arg (ap, int);
+			else
+				num = va_arg (ap, int);
+
+number:
+			if (sign && (stix_intmax_t)num < 0) 
+			{
+				neg = 1;
+				num = -(stix_intmax_t)num;
+			}
+
+			nbufp = sprintn (nbuf, num, base, &tmp);
+			if ((flagc & FLAGC_SHARP) && num != 0) 
+			{
+				if (base == 8) tmp++;
+				else if (base == 16) tmp += 2;
+			}
+			if (neg) tmp++;
+			else if (flagc & FLAGC_SIGN) tmp++;
+			else if (flagc & FLAGC_SPACE) tmp++;
+
+			numlen = nbufp - nbuf;
+			if ((flagc & FLAGC_DOT) && precision > numlen) 
+			{
+				/* extra zeros fro precision specified */
+				tmp += (precision - numlen);
+			}
+
+			if (!(flagc & FLAGC_LEFTADJ) && !(flagc & FLAGC_ZEROPAD) && width > 0 && (width -= tmp) > 0)
+			{
+				while (width--) PUT_CHAR (stix, padc);
+			}
+
+			if (neg) PUT_CHAR (stix, '-');
+			else if (flagc & FLAGC_SIGN) PUT_CHAR (stix, '+');
+			else if (flagc & FLAGC_SPACE) PUT_CHAR (stix, ' ');
+
+			if ((flagc & FLAGC_SHARP) && num != 0) 
+			{
+				if (base == 8) 
+				{
+					PUT_CHAR (stix, '0');
+				} 
+				else if (base == 16) 
+				{
+					PUT_CHAR (stix, '0');
+					PUT_CHAR (stix, 'x');
+				}
+			}
+
+			if ((flagc & FLAGC_DOT) && precision > numlen)
+			{
+				/* extra zeros for precision specified */
+				while (numlen < precision) 
+				{
+					PUT_CHAR (stix, '0');
+					numlen++;
+				}
+			}
+
+			if (!(flagc & FLAGC_LEFTADJ) && width > 0 && (width -= tmp) > 0)
+			{
+				while (width-- > 0) PUT_CHAR (stix, padc);
+			}
+
+			while (*nbufp) PUT_CHAR (stix, *nbufp--); /* output actual digits */
+
+			if ((flagc & FLAGC_LEFTADJ) && width > 0 && (width -= tmp) > 0)
+			{
+				while (width-- > 0) PUT_CHAR (stix, padc);
+			}
+			break;
+
+invalid_format:
+			while (percent < fmt) PUT_CHAR (stix, *percent++);
+			break;
+
+		default:
+			while (percent < fmt) PUT_CHAR (stix, *percent++);
+			/*
+			 * Since we ignore an formatting argument it is no
+			 * longer safe to obey the remaining formatting
+			 * arguments as the arguments will no longer match
+			 * the format specs.
+			 */
+			stop = 1;
+			break;
+		}
+	}
+
+done:
+	return 0;
+
+oops:
+	return (stix_ooi_t)-1;
+}
+#undef PUT_CHAR
diff --git a/stix/lib/main.c b/stix/lib/main.c
index 10390a5..33a5572 100644
--- a/stix/lib/main.c
+++ b/stix/lib/main.c
@@ -329,7 +329,7 @@ printf ("MOD_GETSYM [%s]\n", &buf[0]);
 }
 
 /* ========================================================================= */
-
+ 
 static void log_write (stix_t* stix, int mask, const stix_ooch_t* msg, stix_oow_t len)
 {
 #if defined(_WIN32)
@@ -342,10 +342,10 @@ static void log_write (stix_t* stix, int mask, const stix_ooch_t* msg, stix_oow_
 
 	msgidx = 0;
 
-	while (1)
+	while (len > 0)
 	{
 		ucslen = len;
-		bcslen = STIX_COUNTOF(buf) - len;
+		bcslen = STIX_COUNTOF(buf);
 
 		n = stix_ucstoutf8 (&msg[msgidx], &ucslen, buf, &bcslen);
 		if (n == 0)
@@ -592,7 +592,6 @@ int main (int argc, char* argv[])
 		return -1;
 	}
 
-
 	{
 		stix_oow_t tab_size;
 
diff --git a/stix/lib/stix-prv.h b/stix/lib/stix-prv.h
index e0ca376..49979c0 100644
--- a/stix/lib/stix-prv.h
+++ b/stix/lib/stix-prv.h
@@ -573,8 +573,32 @@ struct stix_compiler_t
 	} mth; 
 };
 
+typedef struct stix_bchbuf_t stix_bchbuf_t;
+struct stix_bchbuf_t
+{
+	stix_bch_t  sbuf[128];
+	stix_bch_t* ptr;
+	stix_oow_t  capa;
+};
+
+typedef struct stix_oochbuf_t stix_oochbuf_t;
+struct stix_oochbuf_t
+{
+	stix_ooch_t  sbuf[128];
+	stix_ooch_t* ptr;
+	stix_oow_t   capa;
+};
+
+struct stix_decoder_t
+{
+	stix_oochbuf_t fltout;
+	stix_bchbuf_t fltfmt;
+};
+
 #endif
 
+
+
 #if defined(STIX_USE_OBJECT_TRAILER)
 	/* let it point to the trailer of the method */
 #	define SET_ACTIVE_METHOD_CODE(stix) ((stix)->active_code = (stix_oob_t*)&(stix)->active_method->slot[STIX_OBJ_GET_SIZE((stix)->active_method) + 1 - STIX_METHOD_NAMED_INSTVARS])
@@ -1299,6 +1323,21 @@ int stix_getprimno (
 	const stix_oocs_t* name
 );
 
+/* ========================================================================= */
+/* fmt.c                                                                     */
+/* ========================================================================= */
+stix_ooi_t stix_bfmtout (
+	stix_t*           stix,
+	const stix_bch_t* fmt,
+	...
+);
+
+
+stix_ooi_t stix_oofmtout (
+	stix_t*            stix,
+	const stix_ooch_t* fmt,
+	...
+);
 /* TODO: remove debugging functions */
 /* ========================================================================= */
 /* debug.c                                                                   */
@@ -1309,6 +1348,8 @@ void print_oocs (const stix_oocs_t* name);
 void print_object (stix_t* stix, stix_oop_t oop);
 void dump_object (stix_t* stix, stix_oop_t oop, const char* title);
 
+
+
 #if defined(__cplusplus)
 }
 #endif
diff --git a/stix/lib/stix-utl.h b/stix/lib/stix-utl.h
index cb868ac..625b440 100644
--- a/stix/lib/stix-utl.h
+++ b/stix/lib/stix-utl.h
@@ -55,7 +55,7 @@ extern "C" {
 
 
 /* ========================================================================= */
-/* stix-utl.c                                                                */
+/* utl.c                                                                */
 /* ========================================================================= */
 stix_oow_t stix_hashbytes (
 	const stix_oob_t* ptr,
@@ -147,6 +147,7 @@ stix_oow_t stix_countbcstr (
 	const stix_bch_t* str
 );
 
+
 #if defined(__cplusplus)
 }
 #endif
diff --git a/stix/lib/stix.c b/stix/lib/stix.c
index 6ff7d28..547f385 100644
--- a/stix/lib/stix.c
+++ b/stix/lib/stix.c
@@ -157,6 +157,16 @@ void stix_fini (stix_t* stix)
 
 	/* deregister all callbacks */
 	while (stix->cblist) stix_deregcb (stix, stix->cblist);
+
+	if (stix->log.ptr) 
+	{
+		/* make sure to flush your log message */
+/* TODO: flush unwritten message */
+
+		stix_freemem (stix, stix->log.ptr);
+		stix->log.capa = 0;
+		stix->log.len = 0;
+	}
 }
 
 stix_mmgr_t* stix_getmmgr (stix_t* stix)
diff --git a/stix/lib/stix.h b/stix/lib/stix.h
index cfc046c..859bcee 100644
--- a/stix/lib/stix.h
+++ b/stix/lib/stix.h
@@ -738,6 +738,7 @@ typedef struct stix_prim_mod_data_t stix_prim_mod_data_t;
  * ========================================================================= */
 #if defined(STIX_INCLUDE_COMPILER)
 typedef struct stix_compiler_t stix_compiler_t;
+typedef struct stix_decoder_t stix_decoder_t;
 #endif
 
 struct stix_t
@@ -757,6 +758,14 @@ struct stix_t
 
 	stix_cb_t* cblist;
 	stix_rbt_t pmtable; /* primitive module table */
+
+	struct
+	{
+		stix_ooch_t* ptr;
+		stix_oow_t len;
+		stix_oow_t capa;
+	} log;
+
 	/* ========================= */
 
 	stix_heap_t* permheap; /* TODO: put kernel objects to here */
@@ -841,11 +850,10 @@ struct stix_t
 
 #if defined(STIX_INCLUDE_COMPILER)
 	stix_compiler_t* c;
+	stix_decoder_t* d;
 #endif
 };
 
-
-
 #if defined(STIX_USE_PROCSTK)
 /* TODO: stack bound check when pushing */
 	#define STIX_STACK_PUSH(stix,v) \
diff --git a/stix/lib/utf8.c b/stix/lib/utf8.c
index 0286062..68672c0 100644
--- a/stix/lib/utf8.c
+++ b/stix/lib/utf8.c
@@ -496,7 +496,7 @@ int stix_utf8toucs (const stix_bch_t* bcs, stix_oow_t* bcslen, stix_uch_t* ucs,
 	}
 }
 
-int stix_ucstoutf8 (const stix_uch_t* ucs, stix_oow_t *ucslen, stix_bch_t* bcs, stix_oow_t* bcslen)
+int stix_ucstoutf8 (const stix_uch_t* ucs, stix_oow_t* ucslen, stix_bch_t* bcs, stix_oow_t* bcslen)
 {
 	if (*ucslen == ~(stix_oow_t)0)
 	{
@@ -514,7 +514,7 @@ int stix_ucstoutf8 (const stix_uch_t* ucs, stix_oow_t *ucslen, stix_bch_t* bcs,
 stix_oow_t stix_ucslen (const stix_uch_t* ucs)
 {
 	const stix_uch_t* ptr = ucs;
-	while  (*ptr) ptr = STIX_INCPTR(const stix_uch_t, ptr, 1);
-	return STIX_SUBPTR(const stix_uch_t, ptr, ucs);
+	while (*ptr) ptr++;
+	return ptr - ucs;
 }
 */
diff --git a/stix/lib/utl.c b/stix/lib/utl.c
index 339b211..bcab9d7 100644
--- a/stix/lib/utl.c
+++ b/stix/lib/utl.c
@@ -1,4 +1,3 @@
-
 /*
  * $Id$
  *
@@ -188,4 +187,3 @@ stix_bch_t* stix_findbchar (const stix_bch_t* ptr, stix_oow_t len, stix_bch_t c)
 
 	return STIX_NULL;
 }
-