diff --git a/string.c b/string.c
index f584627..fbdcff2 100644
--- a/string.c
+++ b/string.c
@@ -353,7 +353,7 @@ void cu_sscanf(char* buf, char* fmt, ...)
     cu_va_start(&ap);
     
     uword idx;
-    uword len,maxLen;
+    uword len, maxLen;
     union {
         iword* iptr;
         uword* uptr;
diff --git a/string.h b/string.h
index b20dfd4..e81f812 100644
--- a/string.h
+++ b/string.h
@@ -35,7 +35,17 @@ void cu_xprints(char* str, uword number);
 iword cu_atoi(char* str,int base);
 uword cu_atou(char* str, int base);
 
+// all integer arguments must be iword or uword, strings - pointers
+// format: d - decimal signed, u - unsigned, x - hexadecimal
+// p - pointer address, s - zero-terminated string.
+// to print % use %% format 
 void cu_sprintf(char* dst, size_t maxLen, const char* fmt, ...);
+
+// all integer arguments must be iword or uword,
+// for strings pass pointer and next size of the buffer
+// example: cu_sscanf((char*)str4, "\"%s\" %d", str5, 8, &val5);
+// where %s is str5 buffer pointer and 8 is size of buffer
+// and &val5 is pointer to iword integer
 void cu_sscanf(char* buf, char* fmt,...);
 
 #endif
\ No newline at end of file
diff --git a/test.c b/test.c
index 4db07a9..895d048 100644
--- a/test.c
+++ b/test.c
@@ -181,8 +181,8 @@ int main()
 
     const char* str4 = "\"test\" 2312";
     char str5[8] = {0};
-    int val5 = 0;
-    cu_sscanf((char*)str4, "\"%s\" %d", str5, &val5);
+    iword val5 = 0;
+    cu_sscanf((char*)str4, "\"%s\" %d", str5, 8, &val5);
     printf("cu_sscanf\t%s\t%u\n", str5, val5);
 
     cutil_exit();