准确设置winsockselect超时

我试图让我的接受呼叫在特定的时间段后超时,我试着在这里的build议:

Winsock接受超时

在这种情况下,我传递一个TIMEVAL结构来select当我打电话时,问题是当我设置tv.tv_usec约40分钟左右,select呼叫立即超时,而不是等待我指定的40分钟。 MSDN指出,select的超时是它将等待的最长时间,我该如何使select或receive在这个超时之前等待特定的时间?

#define WIN32_LEAN_AND_MEAN #include <Windows.h> #include <WinSock2.h> #include <Ws2tcpip.h> #include <cstdio> #include <tchar.h> VOID _tmain( int argc, TCHAR *argv[] ) { WSADATA wsaData = { 0 }; ADDRINFOA hINTs = { 0 }; PADDRINFOA pResult = NULL; SOCKET hServerSocket = INVALID_SOCKET, hClientSocket = INVALID_SOCKET; TIMEVAL tv = { 0 }; INT iReturnStatus = -1; DWORD dwRecvTimeout = 30000, // Milliseconds dwSendTimeout = 30000; // Milliseconds fd_set readFDs = { 0 }; if ( WSAStartup( MAKEWORD( 2, 2 ), &wsaData ) ) { _tprintf_s( TEXT( "WSAStartup Failed\n" ) ); return; } ZeroMemory( &hINTs, sizeof( hINTs ) ); hINTs.ai_family = AF_INET; hINTs.ai_socktype = SOCK_STREAM; hINTs.ai_protocol = IPPROTO_TCP; hINTs.ai_flags = AI_PASSIVE; if ( getaddrinfo( NULL, TEXT( "9001" ), &hINTs, &pResult ) ) { WSACleanup(); _tprintf_s( TEXT( "getaddrinfo Failed\n" ) ); return; } if ( ( hServerSocket = socket( pResult -> ai_family, pResult -> ai_socktype, pResult -> ai_protocol ) ) == INVALID_SOCKET ) { freeaddrinfo( pResult ); WSACleanup(); _tprintf_s( TEXT( "socket Failed\n" ) ); return; } int iResult = bind( hServerSocket, ( pResult -> ai_addr ), pResult -> ai_addrlen ); if ( iResult == SOCKET_ERROR ) { freeaddrinfo( pResult ); closesocket( hServerSocket ); WSACleanup(); _tprintf_s( TEXT( "bind Failed\n" ) ); return; } freeaddrinfo( pResult ); if ( listen( hServerSocket, SOMAXCONN ) ) { closesocket( hServerSocket ); WSACleanup(); _tprintf_s( TEXT( "listen Failed\n" ) ); return; } hClientSocket = INVALID_SOCKET; for ( ;; ) { tv.tv_usec = 2400000000; // microseconds FD_ZERO( &readFDs ); FD_SET( hServerSocket, &readFDs ); _tprintf( "select()\n" ); iReturnStatus = select( 0, &readFDs, NULL, NULL, &tv ); // Select Error if ( iReturnStatus == SOCKET_ERROR ) { _tprintf( "select Failed\n" ); } // Select Success else if ( iReturnStatus ) { // Connection Established On Server Socket if ( FD_ISSET( hServerSocket, &readFDs ) ) { // Accept Client Connection hClientSocket = accept( hServerSocket, NULL, NULL ); if ( hClientSocket == INVALID_SOCKET ) { _tprintf( "accept Failed\n" ); } else { // Set Recv Timeout setsockopt( hClientSocket, SOL_SOCKET, SO_RCVTIMEO, ( const char * ) &dwRecvTimeout, sizeof( dwRecvTimeout ) ); // Set Send Timeout setsockopt( hClientSocket, SOL_SOCKET, SO_SNDTIMEO, ( const char * ) &dwSendTimeout, sizeof( dwSendTimeout ) ); // Process Client Request(s) // HandleConnection( ClientSocket ); } } // Connection Established On Unknown Socket else { _tprintf( "Invalid Socket Returned\n" ); } } // Select Timeout else { _tprintf( "select Timeout\n" ); } } if ( hServerSocket != INVALID_SOCKET ) closesocket( hServerSocket ); return; } 

为什么这样呢?

这是每个定义。

从MSDN逐字:

tv_sec时间间隔,以秒为单位。

tv_usec时间间隔,以微秒为单位。 此值与tv_sec成员结合使用来表示不是秒的倍数的时间间隔

问题是与tv.tv_usec; 手册页中的tv_usec类型为“long”。 值(2400000000) 超出范围,这就是你得到这样的选择系统行为的原因。

如果你想选择等待40分钟,那么确保你使用的是tv.tv_sec。