test, C++ (vc++) - rextester

Language: Layout:

#include <winsock2.h>

void myFunc()
{
    struct SocketRAII
    {
        int theSocket;
        SocketRAII(int s) : theSocket(s) {}
        ~SocketRAII() { closesocket(theSocket); WSACleanup(); }
    };
    
    WSADATA wsaData;
    WSAStartup(MAKEWORD(2, 2), &wsaData);

struct sockaddr_in server_addr;
    memset(&server_addr, 0, sizeof(server_addr));
    server_addr.sin_family = AF_INET;
    server_addr.sin_addr.s_addr = inet_addr("myipaddress");
    server_addr.sin_port = htons(123);

// Doesn't fail when there's no internet connection
    protoent *proto = getprotobyname("udp");
    int s = socket(PF_INET, SOCK_DGRAM, proto->p_proto);
    
    SocketRAII obj(s);
    
    if (s == INVALID_SOCKET) 
       return;

// Doesn't fail when there's no internet connection
    char msg[48] = { 0x08, 0, 0, 0, 0, 0, 0, 0, 0 };
    int iResult = sendto(s, msg, sizeof(msg), 0, (struct sockaddr *) &server_addr, sizeof(server_addr));
    if (iResult == SOCKET_ERROR)
        return;

// Hangs when there's no internet connection
    memset(msg, 0, sizeof(msg));
    struct sockaddr saddr;
    socklen_t saddr_l = sizeof(saddr);
    iResult = recvfrom(s, msg, 48, 0, &saddr, &saddr_l);
}

Show compiler warnings [ + ] Compiler args [ + ] Show input
Compilation time: 1,59 sec, absolute service time: 1,62 sec