BOOL Start(
	LPCTSTR lpszLocalHost,
	UINT nLocalPort,
	UINT nMaxClients,
	DWORD dwOptions
);

BOOL Start(
	LPCTSTR lpszLocalHost,
	UINT nLocalPort,
	DWORD dwOptions
);

BOOL Start(
	UINT nLocalPort,
	DWORD dwOptions
);

BOOL Start(
	UINT nLocalPort
);

The Start method begins listening for client connections on the specified local address and port number. The server is started in its own thread and manages the client sessions independently of the calling thread. All interaction with the server and its client sessions takes place inside the class event handlers.

Parameters

lpszLocalHost

A pointer to a string which specifies the local hostname or IP address address that the server should be bound to. If this parameter is omitted or specifies a NULL pointer an appropriate address will automatically be used. If a specific address is used, the server will only accept client connections on the network interface that is bound to that address.

nLocalPort

The port number the server should use to listen for client connections. The port number used by the application must be unique and multiple instances of a server cannot use the same port number. It is recommended that a port number greater than 5000 be used for private, application-specific implementations.

nMaxClients

The maximum number of client connections that can be established with the server. A value of zero specifies that there should not be any fixed limit on the number of active client connections. This value can be adjusted after the server has been created by calling the Throttle method.

dwOptions

An unsigned integer value that specifies one or more options to be used when creating an instance of the server. For a list of the available options, see Server Option Constants. If this parameter is omitted, the default options for the server instance will be used.

Return Value

If the method succeeds, the return value is non-zero. If the method fails, the return value is zero. To get extended error information, call GetLastError.

Remarks

In most cases, the lpszLocalHost parameter should be omitted or a NULL pointer. On a multihomed system, this will enable the server to accept connections on any appropriately configured network adapter. Specifying a hostname or IP address will limit client connections to that particular address. Note that the hostname or address must be one that is assigned to the local system, otherwise an error will occur.

If an IPv6 address is specified as the local address, the system must have an IPv6 stack installed and configured, otherwise the method will fail.

To listen for connections on any suitable IPv4 interface, specify the special dotted-quad address "0.0.0.0". You can accept connections from clients using either IPv4 or IPv6 on the same socket by specifying the special IPv6 address "::0", however this is only supported on Windows 7 and Windows Server 2008 R2 or later platforms. If no local address is specified, then the server will only listen for connections from clients using IPv4. This behavior is by design for backwards compatibility with systems that do not have an IPv6 TCP/IP stack installed.

The server instance is managed in another thread, and all interaction with the server and active client connections are performed inside the event handlers. To disconnect all active connections, close the listening socket and terminate the server thread, call the Stop method.

Example

// EchoServer implementation
class CEchoServer : public CInternetServer
{
    void OnRead(SOCKET hSocket)
    {
        // Read data sent by the client to the server
        BYTE ioBuffer[1024];
        INT nBytesRead = Read(hSocket, ioBuffer, sizeof(ioBuffer));
            
        // Send a copy of the data back to the client
        if (nBytesRead > 0)
            Write(hSocket, ioBuffer, nBytesRead);
    }
};

int _tmain(int argc, _TCHAR* argv[])
{
    CEchoServer myServer;

    // Start the server listening for connections on port 7000
    if (myServer.Start(7000))
    {
        TCHAR szCommand[128], *pszCommand;

        // Process commands entered by the user at the console
        while (TRUE)
        {
            if ((pszCommand = _fgetts(szCommand, 128, stdin)) == NULL)
                break;

            if (_tcsicmp(pszCommand, _T("quit")) == 0)
                break;
        }

        // Stop the server and terminate all clients
        myServer.Stop();
    }

    return 0;
}

Requirements

Minimum Desktop Platform: Windows 7 Service Pack 1
Minimum Server Platform: Windows Server 2008 R2 Service Pack 1
Header File: cswsock11.h
Import Library: cswskv11.lib
Unicode: Implemented as Unicode and ANSI versions

See Also

EnumClients, Restart, Stop

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