How to determine whether blender background rendering has ended？

Question

For example, I want to automatically shut down my computer after the background rendering is completed, the command I used is

start blender -b "path to the project file" -E BLENDER_EEVEE -o//"exported path" -a

I need to add start at the front, otherwise Blender will enter a pseudo death state after execution. However, with start added, the system will open an additional backend process for Blender to perform rendering operations.

But I don't know how to listen to this process, and when I try to use the subprocess module in Blender Python, it reports an error, The last line in the traceback says:

FileNotFoundError: [winError 2] The system cannot find the specified file

Does anyone know how to solve this situation?

Thanks

Answer 1

A couple other things that look fishy in your example command:

• -o//"exported path" the whole path should be inside the quotation marks: -o "//exported path"
• start shouldn't be necessary, its only purpose is to run a process so that you keep the control of the console instead of waiting for the process to finish. But if you use Blender's CLI correctly, it should return control when done processing AFAIK.

Other than that, I'm a bit confused because, officially:

There is currently no support for using Eevee on headless systems (i.e. without a Display Manager).

Sourbe: Limitations — Blender Manual

This means, unless you fake a display (like shown here), you can't render in command line with Eevee. So you should use CYCLES instead.

And, practically, I haven't seen anyone render using Eevee or Workbench otherwise. But I just did some tests and it... Works?

But I'm using Windows 11's "Terminal" application, and with some addons (clink, wsl2 for GUI Linux, ...), so maybe that's why.