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任何想法爲什麼當服務器在客戶端等待時寫入套接字select,選擇永不完成?使用select來等待客戶端套接字上的數據
我使用c來在套接字之間進行通信。我的客戶端連接到我的服務器罰款。
socket_desc=socket(AF_INET,SOCK_STREAM,0);//create the socket descriptor
client->address.sin_addr.s_addr = inet_addr(ipAddress);
client->address.sin_family = AF_INET;
client->address.sin_port = htons(port);
bind(socket_desc,&address,sizeof(address));
connect(socket_desc, &address, sizeof(address));
當我使用的recv阻塞和監聽數據,一切正常:
int bytesRead = 1;
while(bytesRead){
int bufsize=1024;
char *buffer=malloc(bufsize);
bytesRead = recv(socket_desc, buffer, bufsize, 0);
printf("CLIENT RECV: %s", buffer);
}
如果我嘗試使用選擇,它似乎並沒有讀取任何數據。如果我將STDIN添加到fd_set,我可以強制它從套接字中讀取,但select似乎不會從socket_desc讀取數據中觸發...?
int running = 1;
while(running){
/* wait for something to happen on the socket */
struct timeval selTimeout;
selTimeout.tv_sec = 2; /* timeout (secs.) */
selTimeout.tv_usec = 0; /* 0 microseconds */
fd_set readSet;
FD_ZERO(&readSet);
FD_SET(STDIN_FILENO, &readSet);//stdin manually trigger reading
FD_SET(socket_desc, &readSet);//tcp socket
int numReady = select(3, &readSet, NULL, NULL, &selTimeout);
//IT ONLY GETS PAST SELECT ON RETURN FROM THE KEYBOARD
if(numReady > 0){
char buffer[100] = {'\0'};
int bytesRead = read(socket_desc, &buffer, sizeof(buffer));
printf("bytesRead %i : %s", bytesRead, buffer);
if(bytesRead == 0){
running = FALSE;
printf("Shutdowning client.\n");
}
}
另外值得注意的是,在多個套接字上選擇時,您應該檢查套接字ID是否使用FD_ISSET設置 – vmpstr 2011-01-25 02:28:45