• Algorithms
• Application
• Components
• Database
• Distributed aplication
• DLL
• Errors
• Events
• Hardware
• IDE
• Install Shield
• Internet
• Multimedia
• Object Pascal
• Operational system
• Others
• Security
• Third party
• Win API

TCP/IP: Retrieving Client IP and Host Name

Question:

At client, how can I get the IP address or host name of itself.

Answer:

The following example requires using the Winsock API encapsulated in WinSock.pas.

uses

  WinSock;

procedure GetHostInfo(var Name, Address: string);

var

  WSAData: TWSAData;

  HostEnt: PHostEnt;

begin

  { no error checking...}

  WSAStartup(2, WSAData);

  SetLength(Name, 255);

  Gethostname(PChar(Name), 255);

  SetLength(Name, StrLen(PChar(Name)));

  HostEnt := gethostbyname(PChar(Name));

  with HostEnt^ do

  Address := Format('%d.%d.%d.%d',[

  Byte(h_addr^[0]),

  Byte(h_addr^[1]),

  Byte(h_addr^[2]),

  Byte(h_addr^[3])]);

  WSACleanup;

end;