Remote Procedure Calls

Remote procedure calls are a way to execute a procedure (ex. function) that exists in a different context.

POST /say HTTP/1.1 HOST: api.example.com Content-Type: application/json {"name": "Racey McRacerson"}

/* Signature */ function sayHello(name) { // ... } /* Usage */ sayHello("Racey McRacerson"); |

POST /say HTTP/1.1 HOST: api.example.com Content-Type: application/json {"name": "Racey McRacerson"}

/* Signature */ function clientContact(name) { // ... } /* Usage */ if(request == “/ping} clientContact(request.data);

UDP Communication

DNS Resolution

UDP Code

int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
if (sockfd < 0) {
perror("socket");
}
int optval = 1;
// Let them reuse
setsockopt(sockfd, SOL_SOCKET, SO_REUSEPORT, &optval, sizeof(optval));

struct sockaddr_in addr;
memset(&addr, 0, sizeof(addr));
addr.sin_family = AF_INET;
addr.sin_port = htons((uint16_t)port);
struct hostent *serv = gethostbyname(hostname);

// Timeouts for resending acks and whatnot
struct timeval tv;
tv.tv_sec = 0;
tv.tv_usec = SOCKET_TIMEOUT;
setsockopt(sockfd, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv));