Another UDP Server

// Thanks IBM
// http://www.ibm.com/developerworks/linux/tutorials/l-sock2/section5.html

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <netinet/in.h>

#define BUFFSIZE 255

void Die(const char *mess)
{
    perror(mess);
    exit(1);
}

int main(int argc, char *argv[])
{
    int sock;
    struct sockaddr_in echoserver;
    struct sockaddr_in echoclient;
    char buffer[BUFFSIZE];
    unsigned int clientlen, serverlen;
    int received = 0;

    if (argc != 2) {
        fprintf(stderr, "USAGE: %s <port>\n", argv[0]);
        exit(1);
    }

    /* Create the UDP socket */
    if ((sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
        Die("Failed to create socket");
    }
    /* Construct the server sockaddr_in structure */
    memset(&echoserver, 0, sizeof(echoserver));       /* Clear struct */
    echoserver.sin_family = AF_INET;                  /* Internet/IP */
    echoserver.sin_addr.s_addr = htonl(INADDR_ANY);   /* Any IP address */
    echoserver.sin_port = htons(atoi(argv[1]));       /* server port */

    /* Bind the socket */
    serverlen = sizeof(echoserver);
    if (bind(sock, (struct sockaddr *) &echoserver, serverlen) < 0) {
        Die("Failed to bind server socket");
    }

    /* Run until cancelled */
    while (1) {
        /* Receive a message from the client */
        clientlen = sizeof(echoclient);
        if ((received = recvfrom(sock,
                                 buffer,
                                 BUFFSIZE,
                                 0,
                                 (struct sockaddr *) &echoclient,
                                 &clientlen)
            ) < 0) {
            Die("Failed to receive message");
        }
        fprintf(stderr,
                "Client connected: %s\n",
                inet_ntoa(echoclient.sin_addr));
        /* Send the message back to client */
        if (sendto(sock,
                   buffer,
                   received,
                   0,
                   (struct sockaddr *) &echoclient,
                   sizeof(echoclient)
                  ) != received) {
            Die("Mismatch in number of echo'd bytes");
        }
    }
}