--- /dev/null
+#ifndef _OVERONION_REVERSE_LIB_H
+#define _OVERONION_REVERSE_LIB_H
+
+/* Copy the contents of input_filename to stdout backwards.
+ * input_filename must be a real file, not a pipe. */
+void reverse_file(const char* input_filename);
+
+#endif /* _OVERONION_REVERSE_LIB_H */