initial commit with demo in main.c

include/error.h

@@ -0,0 +1,10 @@
+#pragma once
+
+#include <stdio.h>
+#include <stdbool.h>
+
+#define eprintf(fmt, ...) \
+	fprintf(stderr, "[ERROR] " fmt "\n", ##__VA_ARGS__)
+
+#define RCODE_FAILURE false
+#define RCODE_SUCCESS true