INT GetClientPort(
	SOCKET hSocket
);

INT GetClientPort();

Returns the remote port number used by the client to establish the connection.

Parameters

hSocket

An optional parameter that specifies the handle to the client socket. If this parameter is omitted, the socket handle for the active client session will be used. If this method is called outside of a server event handler, the socket handle must be specified.

Return Value

If the method succeeds, the return value is the port number. If the method fails, the return value is INET_ERROR. To get extended error information, call GetLastError.

Remarks

The GetClientPort method returns the remote port number that the client is bound to. Note that this is not the port number that the server is using to listen for connections, it is the port number that the client is bound to on the remote host. Typically this is an ephemeral port, either in the range of 1025 through 5000, or greater than 32768, depending on the client operating system.

If this method is called within the OnAccept event handler, providing the server socket handle as the hSocket parameter will return the port number of the client that is attempting to establish the connection.

It is not recommended that you use the client port number for anything other than informational and logging purposes. Do not make any assumptions about the specific port number or range of port numbers that a client is using when establishing a connection to the server. The ephemeral port number that a client is bound to can vary based on the client operating system.

Requirements

Minimum Desktop Platform: Windows 7 (Service Pack 1)
Minimum Server Platform: Windows Server 2008 R2 (Service Pack 1)
Header: Include cswsock10.h
Import Library: cswskv10.lib

See Also

GetClientAddress, OnAccept, OnConnect

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