diff --git a/src/stdio.c b/src/stdio.c
index 687686b..6b4c60d 100644
--- a/src/stdio.c
+++ b/src/stdio.c
@@ -7,11 +7,11 @@
 
 
 
-static int32_t rtstring_output_handler(void *user, const char *data, size_t size)
+static int32_t rtstring_output_handler(void* user, const char* data, size_t size)
 {
-	string_descriptor_t* str_descriptor = (string_descriptor_t*)user;
+	string_descriptor_t* const str_descriptor = (string_descriptor_t*)user;
 
-	size_t len = size < (str_descriptor->len - 1) ? size : (str_descriptor->len - 1);
+	const size_t len = size < (str_descriptor->len - 1) ? size : (str_descriptor->len - 1);
 
 	if (len)
 	{
@@ -27,7 +27,7 @@
 
 
 
-int32_t sprintf(char *str, const char *format, ...)
+int32_t sprintf(char* str, const char* format, ...)
 {
 	va_list args;
 	va_start(args, format);	
@@ -40,20 +40,27 @@
 }
 
 
-int32_t snprintf(char *str, size_t n, const char *format, ...)
+int32_t snprintf(char* str, size_t n, const char* format, ...)
 {
-	va_list args;
-	va_start(args, format);	
+	if (n > 0)
+	{
+		va_list args;
+		va_start(args, format);	
 
-	string_descriptor_t str_descriptor = {str, n};
-	const int32_t rv = rtprintf(rtstring_output_handler, &str_descriptor, format, args);
+		string_descriptor_t str_descriptor = {str, n};
+		const int32_t rv = rtprintf(rtstring_output_handler, &str_descriptor, format, args);
 
-	va_end(args);
-	return rv;
+		va_end(args);
+		return rv;
+	}
+	else
+	{
+		return 0;
+	}
 }
 
 
-int32_t vsprintf(char *str, const char *format, va_list args)
+int32_t vsprintf(char* str, const char* format, va_list args)
 {
 	string_descriptor_t str_descriptor = {str, -1};
 	return rtprintf(rtstring_output_handler, &str_descriptor, format, args);
@@ -61,10 +68,17 @@
 
 
 
-int32_t vsnprintf(char *str, size_t n, const char *format, va_list args)
+int32_t vsnprintf(char* str, size_t n, const char* format, va_list args)
 {
-	string_descriptor_t str_descriptor = {str, n};
-	return rtprintf(rtstring_output_handler, &str_descriptor, format, args);
+	if (n > 0)
+	{
+		string_descriptor_t str_descriptor = {str, n};
+		return rtprintf(rtstring_output_handler, &str_descriptor, format, args);
+	}
+	else
+	{
+		return 0;
+	}
 }
 
 
@@ -85,14 +99,21 @@
 
 int32_t isnprintf(char *str, size_t n, const char *format, ...)
 {
-	va_list args;
-	va_start(args, format);	
+	if (n > 0)
+	{
+		va_list args;
+		va_start(args, format);	
 
-	string_descriptor_t str_descriptor = {str, n};
-	int32_t rv = rtiprintf(rtstring_output_handler, &str_descriptor, format, args);
+		string_descriptor_t str_descriptor = {str, n};
+		int32_t rv = rtiprintf(rtstring_output_handler, &str_descriptor, format, args);
 
-	va_end(args);
-	return rv;
+		va_end(args);
+		return rv;
+	}
+	else
+	{
+		return 0;
+	}
 }
 
 
@@ -103,10 +124,16 @@
 }
 
 
-
 int32_t ivsnprintf(char *str, size_t n, const char *format, va_list args)
 {
-	string_descriptor_t str_descriptor = {str, n};
-	return rtiprintf(rtstring_output_handler, &str_descriptor, format, args);
+	if (n > 0)
+	{
+		string_descriptor_t str_descriptor = {str, n};
+		return rtiprintf(rtstring_output_handler, &str_descriptor, format, args);
+	}
+	else
+	{
+		return 0;
+	}
 }