<分区>
我正在使用 TCP 套接字在设备之间进行连接。我关闭连接的一侧 - 服务器端。我正在使用 setsockopt 和超时。根据我的理解，在这种情况下，客户端套接字上的 Aread 调用应该返回 -1。但它返回 0。有什么我需要修改的吗？ 在下面粘贴客户端代码。
void* socketClientLoop(void* arg)
{
//struct socketArgs* sockArg = (struct socketArgs *)arg;
char server_address[20] , *strtokResult;
strcpy(server_address,"192.168.43.217"/*sockArg->server_address*/);
printf("\nsocket : server address in clientLoop = %s\n",server_address);
struct sockaddr_in addr = { 0 };
int s, status, distance;
int distanceFromSocket = 0;//sockArg->distance;
char gpsMessage[128], dist[16];
int flag = true, writeFlag = false;
struct timeval tv;
while(true)
{
printf("socket : loop started\n");
flag = true;
// allocate a socket
printf("socket : loop started1\n");
s = socket(AF_INET, SOCK_STREAM, 0);
printf("socket : loop started2\n");
if(s<0) perror("socket error in client loop");
// set the connection parameters (who to connect to)
addr.sin_family = AF_INET;
addr.sin_port = htons(5000);
if(inet_pton(AF_INET, server_address, &addr.sin_addr)<=0)
{
printf("\n socket : inet_pton error occured\n");
return 0;
}
tv.tv_sec = 15; // 30 seconds
tv.tv_usec = 0; // microsecs, set to 0 (or ...)
setsockopt(s, SOL_SOCKET, SO_RCVTIMEO, (const char*)&tv,sizeof(struct timeval));
// connect to server
status = connect(s, (struct sockaddr *)&addr, sizeof(addr));
if(status<0) perror("socket status error in client loop");
// send a message
if( status == 0 ) {
while(flag)
{
sleep(5);
memset(gpsMessage,0,sizeof(gpsMessage));
status = read(s,gpsMessage, 128);
if(!strncmp(gpsMessage,"connected",9)) writeFlag = true;
else writeFlag = false;
strtokResult = strtok(gpsMessage,":");
if(strtokResult)
{
strtokResult = strtok(0,":");
if(strtokResult)
{
strcpy(dist,strtokResult);
sscanf(dist,"%d",&distance);
}
}
printf("dist = %d\n", distance);
printf("socket : clientLoop did not exited\n");
if(distance == 2*distanceFromSocket)
{
/*pthread_mutex_lock(&fill_mutex);
pthread_cond_signal(&cond_var);
pthread_mutex_unlock(&fill_mutex);*/
}
if(writeFlag)
{
socketPrepareMessageToSend(gpsMessage);
status = write(s,gpsMessage , strlen(gpsMessage));
//if(status < 0) flag=false;
}
//strcpy(gpsMessage,"No Ring");
status = read(s,gpsMessage, 128);
printf("bytes_read %d \n",status);
if(status < 0)
{
printf("set loopflag\n");
flag=false;
writeFlag=false;
}
else
{
writeFlag=true;
printf("ring no ring = %s\n",gpsMessage);
if(!strcmp(gpsMessage,"Ring"))
{
printf("SOCKET RING\n");
system("espeak -ven+f3 -k5 -s150 \"I've just picked up a fault in the AE35 unit\"");
}
else printf("wrongoption\n");
}
}
}
if( status < 0 ) perror("uh oh");
printf("socket : clientLoop exited\n");
close(s);
printf("socket : end of loop\n");
}
}