diff --git a/qse/lib/awk/fnc.c b/qse/lib/awk/fnc.c
index 0538ac1d..3408af29 100644
--- a/qse/lib/awk/fnc.c
+++ b/qse/lib/awk/fnc.c
@@ -23,10 +23,6 @@
 static int fnc_close   (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
 static int fnc_fflush  (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
 static int fnc_index   (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
-static int fnc_gsub    (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
-static int fnc_sub     (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
-static int fnc_match   (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
-static int fnc_sprintf (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
 
 static int fnc_sin     (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
 static int fnc_cos     (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
@@ -67,10 +63,10 @@ static qse_awk_fnc_t sysfnctab[] =
 	{ {QSE_T("split"),   5}, 0, { {2,     3, QSE_T("vrx")}, qse_awk_fnc_split,    0 }, QSE_NULL},
 	{ {QSE_T("tolower"), 7}, 0, { {1,     1, QSE_NULL},     qse_awk_fnc_tolower,  0 }, QSE_NULL},
 	{ {QSE_T("toupper"), 7}, 0, { {1,     1, QSE_NULL},     qse_awk_fnc_toupper,  0 }, QSE_NULL},
-	{ {QSE_T("gsub"),    4}, 0, { {2,     3, QSE_T("xvr")}, fnc_gsub,             0 }, QSE_NULL},
-	{ {QSE_T("sub"),     3}, 0, { {2,     3, QSE_T("xvr")}, fnc_sub,              0 }, QSE_NULL},
-	{ {QSE_T("match"),   5}, 0, { {2,     3, QSE_T("vxv")}, fnc_match,            0 }, QSE_NULL},
-	{ {QSE_T("sprintf"), 7}, 0, { {1, A_MAX, QSE_NULL},     fnc_sprintf,          0 }, QSE_NULL},
+	{ {QSE_T("gsub"),    4}, 0, { {2,     3, QSE_T("xvr")}, qse_awk_fnc_gsub,     0 }, QSE_NULL},
+	{ {QSE_T("sub"),     3}, 0, { {2,     3, QSE_T("xvr")}, qse_awk_fnc_sub,      0 }, QSE_NULL},
+	{ {QSE_T("match"),   5}, 0, { {2,     3, QSE_T("vxv")}, qse_awk_fnc_match,    0 }, QSE_NULL},
+	{ {QSE_T("sprintf"), 7}, 0, { {1, A_MAX, QSE_NULL},     qse_awk_fnc_sprintf,  0 }, QSE_NULL},
 
 	/* math functions */
 	{ {QSE_T("sin"),     3}, 0, { {1,     1, QSE_NULL},     fnc_sin,              0 }, QSE_NULL},
@@ -1086,17 +1082,17 @@ oops:
 	return -1;
 }
 
-static int fnc_gsub (qse_awk_rtx_t* run, const qse_awk_fnc_info_t* fi)
+int qse_awk_fnc_gsub (qse_awk_rtx_t* run, const qse_awk_fnc_info_t* fi)
 {
 	return __substitute (run, 0);
 }
 
-static int fnc_sub (qse_awk_rtx_t* run, const qse_awk_fnc_info_t* fi)
+int qse_awk_fnc_sub (qse_awk_rtx_t* run, const qse_awk_fnc_info_t* fi)
 {
 	return __substitute (run, 1);
 }
 
-static int fnc_match (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi)
+int qse_awk_fnc_match (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi)
 {
 	qse_size_t nargs;
 	qse_awk_val_t* a0, * a1;
@@ -1196,7 +1192,7 @@ static int fnc_match (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi)
 	return 0;
 }
 
-static int fnc_sprintf (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi)
+int qse_awk_fnc_sprintf (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi)
 {	
 	qse_size_t nargs;
 	qse_awk_val_t* a0;
diff --git a/qse/lib/awk/fnc.h b/qse/lib/awk/fnc.h
index 22fcf0f0..86bb5017 100644
--- a/qse/lib/awk/fnc.h
+++ b/qse/lib/awk/fnc.h
@@ -42,11 +42,15 @@ extern "C" {
 
 qse_awk_fnc_t* qse_awk_findfnc (qse_awk_t* awk, const qse_cstr_t* name);
 
-int qse_awk_fnc_length (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
-int qse_awk_fnc_substr (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
-int qse_awk_fnc_split (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
+int qse_awk_fnc_length  (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
+int qse_awk_fnc_substr  (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
+int qse_awk_fnc_split   (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
+int qse_awk_fnc_match   (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
+int qse_awk_fnc_gsub    (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
+int qse_awk_fnc_sub     (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
 int qse_awk_fnc_tolower (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
 int qse_awk_fnc_toupper (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
+int qse_awk_fnc_sprintf (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t* fi);
 
 #ifdef __cplusplus
 }
diff --git a/qse/lib/awk/mod-str.c b/qse/lib/awk/mod-str.c
index 2ab19f16..45b59b38 100644
--- a/qse/lib/awk/mod-str.c
+++ b/qse/lib/awk/mod-str.c
@@ -294,9 +294,15 @@ struct fnctab_t
 	qse_awk_mod_sym_fnc_t info;
 };
 
+/* TODO: match. let str::match() change str::RLENGTH and str::RSTART */
+/* TODO: index. reuse fnc_index() in fnc.c */
+
+#define A_MAX QSE_TYPE_MAX(int)
+
 static fnctab_t fnctab[] =
 {
 	/* keep this table sorted for binary search in query(). */
+	{ QSE_T("gsub"),      { { 2, 3, QSE_T("xvr")},  qse_awk_fnc_gsub,      0 } },
 	{ QSE_T("index"),     { { 2, 3, QSE_NULL },     fnc_index,             0 } },
 	{ QSE_T("isalnum"),   { { 1, 1, QSE_NULL },     fnc_isalnum,           0 } },
 	{ QSE_T("isalpha"),   { { 1, 1, QSE_NULL },     fnc_isalpha,           0 } },
@@ -312,10 +318,13 @@ static fnctab_t fnctab[] =
 	{ QSE_T("isxdigit"),  { { 1, 1, QSE_NULL },     fnc_isxdigit,          0 } },
 	{ QSE_T("length"),    { { 1, 1, QSE_NULL },     qse_awk_fnc_length,    0 } },
 	{ QSE_T("ltrim"),     { { 1, 1, QSE_NULL },     fnc_ltrim,             0 } },
+	{ QSE_T("match"),     { { 2, 3, QSE_T("vxv") }, qse_awk_fnc_match,     0 } },
 	{ QSE_T("normspace"), { { 1, 1, QSE_NULL },     fnc_normspace,         0 } },
+	{ QSE_T("printf"),    { { 1, A_MAX, QSE_NULL }, qse_awk_fnc_sprintf,   0 } },
 	{ QSE_T("rindex"),    { { 2, 3, QSE_NULL },     fnc_rindex,            0 } },
 	{ QSE_T("rtrim"),     { { 1, 1, QSE_NULL },     fnc_rtrim,             0 } },
 	{ QSE_T("split"),     { { 2, 3, QSE_T("vrx") }, qse_awk_fnc_split,     0 } },
+	{ QSE_T("sub"),       { { 2, 3, QSE_T("xvr") }, qse_awk_fnc_sub,       0 } },
 	{ QSE_T("substr"),    { { 2, 3, QSE_NULL },     qse_awk_fnc_substr,    0 } },
 	{ QSE_T("tolower"),   { { 1, 1, QSE_NULL },     qse_awk_fnc_tolower,   0 } },
 	{ QSE_T("toupper"),   { { 1, 1, QSE_NULL },     qse_awk_fnc_toupper,   0 } },