How to determine if the current session is remotely controlled

Call GetSystemMetrics() with the Flag SM_REMOTECONTROL to determine
if the current session is remotely controlled.
Its value is TRUE if the current session is remotely controlled;
FALSE otherwise.

function IsRemotelyControlled: Boolean;
const
SM_REMOTECONTROL = $2001; // from WinUser.h
begin
Result := Boolean(GetSystemMetrics(SM_REMOTECONTROL));
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
if IsRemotelyControlled then
ShowMessage('Remotely controlled.')
else
ShowMessage('Not Remotely controlled.')
end;