http://*.com/questions/2043/can-a-windows-dll-retrieve-its-own-filename

A windows exe file has access to the command string which invoked it, including its path and filename. eg. 

C:\MyApp\MyApp.exe --help.

But this is not so for a dll invoked via LoadLibrary. Does anyone know of a way for a dll to find out what its path and filename is?

Specifically I‘m interested in a Delphi solution, but I suspect that the answer would be pretty much the same for any language.

I think you‘re looking for GetModuleFileName.

{
  If you are working on a DLL and are interested in the filename of the
  DLL rather than the filename of the application, then you can use this function:
}

function GetModuleName: string;
var
  szFileName: array[0..MAX_PATH] of Char;
begin
  FillChar(szFileName, SizeOf(szFileName), #0);
  GetModuleFileName(hInstance, szFileName, MAX_PATH);
  Result := szFileName;
end;

Can a windows dll retrieve its own filename?