this also

examples/sample.source.MHEG5/config.h

+
+extern int opt_debug;
+
+#define	ASN_DEBUG(fmt, args...)	do {		\
+		if(opt_debug < 2) break;	\
+		fprintf(stderr, fmt, ##args);	\
+		fprintf(stderr, " (%s:%d)\n",	\
+			__FILE__, __LINE__);	\
+	} while(0)
+