Constants initialized with expressions are not allowed by all compilers.
#define DEFAULT_MTU 1000
-static const long USEC_PER_SEC = 1000000;
-static const long NSEC_PER_SEC = 1000000000;
-static const int DEFAULT_USER_TIMEOUT = 60; // sec
-static const long START_RTO = 1 * USEC_PER_SEC; // usec
-static const long MAX_RTO = 3 * USEC_PER_SEC; // usec
+#define USEC_PER_SEC 1000000L
+#define NSEC_PER_SEC 1000000000L
+#define DEFAULT_USER_TIMEOUT 60
+#define START_RTO (1 * USEC_PER_SEC)
+#define MAX_RTO (3 * USEC_PER_SEC)
struct hdr {
uint16_t src; // Source port