Modifying an open file from another execuatble

[David Muscat]

I would like to run an executable from the tools provided in Textpad. Then, based on inputs from this executable, I would like to modify the currently open file. Up to now I only need to add some text to the current cursor location. Has anyone done this, if it can be done? I see that textpad can provide a pointer to the current document. But Im not sure how I can use this through my executable which is written using Visual C++

Thanks
David