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POSending/receiving weird data
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copied!<p>Im sending data on network via sockets like this: (broadcast)</p> <pre><code> void sendBroad(char *dstIP, char *localIP, char *localMAC) { int sock; /* Socket */ struct sockaddr_in broadcastAddr; /* Broadcast address */ int broadcastPermission; /* Socket opt to set permission to broadcast */ unsigned int dataLen; char data[100]={0}; strcat(data, localIP); strcat(data, " "); strcat(data, localMAC); strcat(data, " "); /* Create socket for sending/receiving datagrams */ if ((sock = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) perror("socket() failed"); /* Set socket to allow broadcast */ broadcastPermission = 1; if (setsockopt(sock, SOL_SOCKET, SO_BROADCAST, (void *) &broadcastPermission, sizeof(broadcastPermission)) < 0) perror("setsockopt() failed"); /* Construct local address structure */ memset(&broadcastAddr, 0, sizeof(broadcastAddr)); /* Zero out structure */ broadcastAddr.sin_family = AF_INET; /* Internet address family */ broadcastAddr.sin_addr.s_addr = inet_addr(dstIP); /* Broadcast IP address */ broadcastAddr.sin_port = htons(BroadcastPort); /* Broadcast port */ dataLen = strlen(data); int j; for (j=0; j<1; j++) /* 3krat a dost */ { /* Broadcast localIP in datagram to clients */ if (sendto(sock, data, dataLen, 0, (struct sockaddr *) &broadcastAddr, sizeof(broadcastAddr)) != dataLen) perror("sendto() sent a different number of bytes than expected"); } /* NOT REACHED */ } </code></pre> <p>but I always get some weird chars in the begining when receiving, like:</p> <pre><code>X.?192.168..... </code></pre> <p>When I try to send this data 6 times, just once I get data starting with 192..., other 5 strings starts with those weird chars. Any idea what is happening here?</p> <p>Thanks</p>

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