// nbcode "packet" startstruct packet_t {  sc_uint<32> src_addr;  sc_uint<32> dest_addr;  sc_uint<16> msg_length;  char        msg[1024];};// nbcode "packet" end// nbcode "out" start//define an ostream for a packet objectostream& operator<<(ostream& os, const packet_t& p) {  os << "{\n"     << "   src_addr: " << p.src_addr << "\n"     << "   dest_addr: " << p.dest_addr << "\n"     << "   msg_length: " << p.msg_length << "\n"     << "   msg {\n"     << "     " << p.msg  << "\n"     << "   }\n}" << endl;  return os;}// nbcode "out" end