GetOpenFileName Focus

I have two simple programs written in C running at the same time. The first program has a GUI window, while the second program has no window (hidden).

The first program (GUI) sends a TCP command to the second program (hidden), and the second program opens a file dialogue using Win32 API GetOpenFileNameA(). The issue is this file dialogue box shows behind the GUI window.

Question:

How do I run GetOpenFileNameA() and force focus on it?

        OPENFILENAMEA ofn;
        ZeroMemory(&ofn, sizeof(OPENFILENAME));
        ofn.lStructSize = sizeof(OPENFILENAME);
        ofn.hwndOwner = NULL;
        ofn.lpstrFile = FILE_PATH;
        ofn.nMaxFile = sizeof(FILE_PATH);
        ofn.lpstrFilter = "All Files\0*.*\0";
        ofn.nFilterIndex = 1;
        ofn.lpstrFileTitle = NULL;
        ofn.nMaxFileTitle = 0;
        ofn.lpstrInitialDir = NULL;
        ofn.Flags = OFN_PATHMUSTEXIST | OFN_FILEMUSTEXIST;

        if (GetOpenFileNameA(&ofn)) {
            return FILE_PATH;
        }

>Solution :

You could probably force it on top by providing a callback function for messages intended for the dialog box:

UINT_PTR OFNHookProcOldStyle(HWND hdlg, UINT uiMsg, WPARAM wParam, LPARAM lParam)
{
    BringWindowToTop(hdlg); // or SetWindowPos 
    return 0;
}

Then set

ofn.lpfnHook = OFNHookProcOldStyle;

before calling GetOpenFileNameA.