Add *scanf to header

include/bits/stdio.h

@@ -7,5 +7,8 @@ int fprintf(FILE * stream, const char * fmt, ...);
 int printf(const char * fmt, ...);
 int snprintf(char *s, size_t n, const char * fmt, ...);
 int sprintf(char *s, const char * fmt, ...);
+int fscanf(FILE * stream, const char * fmt, ...);
+int scanf(const char * fmt, ...);
+int sscanf(const char * input, const char * fmt, ...);
 
 #endif /* _BITS_STDIO_H */