Implements a WhoIs or Nickname server.

TIdWhoIsServer = class(TIdTCPserver)

TIdWhoIsServer helps developers write implementations the Nickname or Whois protocol (RFC 954) as a server. Whois is a simple database query system that is commonly used for consulting domain registration records although it can be used for other simple directory services.

Port number used to listen for new connections.

property DefaultPort;

DefaultPort is an Integer property that identifies the port number used for new socket bindings created by the server. The value of DefaultPort is read from and written to Bindings.DefaultPort. The default value for DefaultPort is IdPORT_WHOIS, as assigned in the Create constructor.

Constructor for the object instance.

constructor Create(AOwner: TComponent); override;

Create is the constructor for the TIdWhoIsServer object instance. Create calls the inherited Create method, and sets the value of DefaultPort to the standard port number used for the WhoIs protocol (IdPORT_WHOIS).

Event handler triggered during execution of a WhoIs query.

property OnCommandLookup: TGetEvent;

OnCommandLookup is the TGetEvent event handler triggered when a client makes a query to the WhoIs server. OnCommandLookup is used during execution of the threaded client connection, and allows the server to implement the specifics operations needed to resolve the WhoIs query. OnCommandLookup is the event handler used to respond to execution of the TIdWHOIS.WhoIs method on the client.

AThread is the thread for the client connection. ALookup is the domain query to be resolved by the WhoIs server.

Note: A server implementation must assign a procedure to the event handler to allow responding to the event notification. The procedure is responsible for all aspects of resolving the WhoIs query in ALookup, and writing appropriate return values or error messages to the client connection in AThread.