Added resumable loading, along with signal handling.

This version can store state after receiving SIGINT.
This is achieved by polling FIFO read state;

Macro.hpp

@@ -0,0 +1,5 @@
+#pragma once
+#include <unistd.h>
+#include <string>
+
+#define ERR() if (errno != 0) perror((string{ "(" } + __FILE__ + ":" + to_string(__LINE__) + ")" + " "  + __PRETTY_FUNCTION__).c_str()), errno = 0