Recently I am working on some projects that I want to control blender modeling outside blender. Currently, I am able to do this with the UI version, and running on a computer with X-window, so the UI is totally fine. Here is a simple description of what I am doing right now: say I have a python process, randomly decide what action to take, e.g., move a vertex, do the subdivision, and so on, on an existing mesh.
The question is, I now have access to a server that does not have X-window, I am wondering how I can do the thing in background mode.
Since until so far, I am aware most of the headless mode is for rendering.
If I did not ask blender to render something, it just quit right after.
Following is the screenshot:

Is there any good approach that I can load the blend file, and then keep the blender up (not quit immediately), so that my script can send the follow up action to it?
thx a lot