林通過套接字這樣發送網絡數據:(廣播)發送/接收怪異數據
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 */
}
但在接收時,好像我總是得到一些奇怪的字符在開始時:
X.?192.168.....
當我嘗試發送這些數據6次時,只要我從192 ...開始獲取數據,其他5個字符串就會從這些奇怪的字符開始。有什麼想法發生在這裏?
感謝
downvote,這有多酷...... – shaggy
我認爲這是因爲你已經將你的問題標記爲與網絡有關,但實際上它沒有任何關係 - 你的**問題**與字符串操縱和聯網只是操縱字符串的最終目標。 –
他不知道問題是什麼,因此問題和標籤。 – Erix