服务端为上位机部分。客户端为下位机部分，下位机有多个MCU，所以就会有不同的IP地址。上位机实现接收下位机的信息，并区别不同的IP发来的信息。通信端口5000
服务端：IP设置为196.168.1.100
int sock_fd = socket(PF_INET, SOCK_DGRAM, 0);
if(sock_fd < 0)
{
printf("error: Create Socket Failed!");
return -1;
}
struct sockaddr_in sock_addr;
sock_addr.sin_family = AF_INET;
sock_addr.sin_port = htons(5000);
sock_addr.sin_addr.s_addr = htonl(INADDR_ANY);
memset(sock_addr.sin_zero, 0x00, 8);
try
{
if(bind(sock_fd, (struct sockaddr *)&sock_addr, sizeof(struct sockaddr)) != 0) //绑定
{
printf("error: Bind Socket Failed!");
res = -1;
throw res;
}
char buf[256];
int recvslen;
struct sockaddr_in from;
uint32_t fromlen = sizeof(struct sockaddr);
while(1)
{
if((recvslen = recvfrom(sock_fd, recvs, 256, 0, (struct sockaddr *)&from , &fromlen)) == -1)
{
printf("error: Receiving Failed!");
res = -1;
throw res;
}
else
{
if(recvslen < 256)
*(recvs+recvslen) = ‘\0‘;
else
*(recvs+255) = ‘\0‘;
if (from.sin_addr.s_addr == inet_addr(196.168.1.2)){ //根据from的IP地址来确定是接收的哪个IP发来的信息
printf("Received data:\n[%s] from 196.168.1.2\n",recvs);
}
}
}
}
catch(...)
{
printf("error catched~");
}
客户端：以IP 196.168.1.2为例
int sock_fd = socket(PF_INET, SOCK_DGRAM, 0);
if(sock_fd < 0)
{
printf("error: Create Socket Failed!");
return -1;
}
struct sockaddr_in addrTo;
addrTo.sin_family = AF_INET;
addrTo.sin_port = htons(5000);
addrTo.sin_addr.s_addr = htonl("196.168.1.100"); //服务端的地址
memset(addrTo.sin_zero, 0x00, 8);
try
{
char buf[256] = "This is from 196.168.1.2";
int n;
struct sockaddr_in to;
uint32_t tolen = sizeof(struct sockaddr);
while(1)
{
if((n= recvfrom(sock_fd, recvs, 5000, 0, (struct sockaddr *)&addrTo, &tolen)) == -1)
{
printf("error: Receiving Failed!");
res = -1;
throw res;
}
else if (n > 0)
{
printf("Send data to 196.168.1.100\n");
}
}
}
catch(...)
{
printf("error catched~");
}