diff --git a/src/include/stdio.h b/src/include/stdio.h
index b5fd5dc1..eac89009 100644
--- a/src/include/stdio.h
+++ b/src/include/stdio.h
@@ -6,6 +6,7 @@
 int putchar(char c);
 int printf(const char* format, ...);
 int vprintf(const char* format, va_list arg);
-
+int sprintf(char*, const char*, ...);
+int vsprintf(char*, const char*, va_list arg);
 
 #endif