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SDK Script udpserver.are

udpserver.are
/* DESC: This script implements an UDP server which is able to receive messages.
 * Copyright (C) 2012-2016 NetModule AG, Switzerland
 */
 
void usage()
{
    printf("usage: udpserver.are <port>\n");
    exit(1);
}
 
if (argc < 2) {
    usage();
}
 
PORT = (int) argv[1];
 
sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
if (sock < 0) {
    nb_syslog("Unable to open socket");
    exit(1);
}
 
/* bind socket to 1st LAN interface */
addr = nb_ifc_address("LAN1");
ret = bind(sock, PORT, addr);
if(ret == -1) {
    nb_syslog("Unable to bind to port %d", PORT);
    close(sock);
    exit(1);
}
 
nb_syslog("Listening for messages on port %d", PORT);
 
while (1) {
    msg = recvmsg(sock, 3);
    if (is_void(msg)) continue;
 
    data = struct_get(msg, "data");
    from = struct_get(msg, "from");
 
    if (left(data, 4) == "quit") {
        nb_syslog("Received quit, terminating");
        break;
    } else if (data != "") {
        nb_syslog("Received message '%s' from %s", data, from);
    }
}
 
close(sock);
exit(0);