Mega Code Archive
Resolve IP numbers to Host address
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Title: Resolve IP numbers to Host address
Question: Describe a function that shows how to resolve IP numbers to Host address
Answer:
uses winsock
-------
function IPAddrToName(IPAddr : String): String;
var
SockAddrIn: TSockAddrIn;
HostEnt: PHostEnt;
WSAData: TWSAData;
begin
WSAStartup($101, WSAData);
SockAddrIn.sin_addr.s_addr:= inet_addr(PChar(IPAddr));
HostEnt:= gethostbyaddr(@SockAddrIn.sin_addr.S_addr, 4, AF_INET);
if HostEntnil then
begin
result:=StrPas(Hostent^.h_name)
end
else
begin
result:='';
end;
end;
//Example:
procedure TForm1.Button1Click(Sender: TObject);
begin
Label1.Caption:=IPAddrToName(Edit1.Text);
end;
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