Send a broadcast udp message using c / obj-c

bcastpacket.m

#include <netinet/in.h>
#include <sys/socket.h>
#include <unistd.h>
#include <arpa/inet.h>

- (void)sendBroadcastPacket {
    // Open a socket
    int sd = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
    if (sd<=0) {
        NSLog(@"Error: Could not open socket");
        return;
    }
    
    // Set socket options
    // Enable broadcast
    int broadcastEnable=1;
    int ret=setsockopt(sd, SOL_SOCKET, SO_BROADCAST, &broadcastEnable, sizeof(broadcastEnable));
    if (ret) {
        NSLog(@"Error: Could not open set socket to broadcast mode");
        close(sd);
        return;
    }
    
    // Since we don't call bind() here, the system decides on the port for us, which is what we want.    
    
    // Configure the port and ip we want to send to
    struct sockaddr_in broadcastAddr; // Make an endpoint
    memset(&broadcastAddr, 0, sizeof broadcastAddr);
    broadcastAddr.sin_family = AF_INET;
    inet_pton(AF_INET, "239.255.255.250", &broadcastAddr.sin_addr); // Set the broadcast IP address
    broadcastAddr.sin_port = htons(1900); // Set port 1900
    
    // Send the broadcast request, ie "Any upnp devices out there?"
    char *request = "M-SEARCH * HTTP/1.1\r\nHOST:239.255.255.250:1900\r\nMAN:\"ssdp:discover\"\r\nST:ssdp:all\r\nMX:1\r\n\r\n";
    ret = sendto(sd, request, strlen(request), 0, (struct sockaddr*)&broadcastAddr, sizeof broadcastAddr);
    if (ret<0) {
        NSLog(@"Error: Could not open send broadcast");
        close(sd);
        return;        
    }
    
    // Get responses here using recvfrom if you want...
    close(sd);
}

REALLY SUPER. Need more in detail the other files i mean
.h,.m class files