CoreGraphics.CGWindowListCreateImage() failed when running as a system process.

General information:

• OS name: macOS Catalina
• OS version: 10.15
• OS architecture: 64 bits
• Resolutions:
  • Monitor 1: 1920x1080
• Python version: 3.7.3
• MSS version: 3.2.0

Description of the warning/error

I’m trying to run my python program as a launchd daemon process since its a REST flask app that needs to be running at all times and needs to have the ability to relaunch if the macOS gets rebooted.

One of the endpoints allows me to grab a screenshot of the current monitor. I really like to use your library for the lower level performance… but running as a launchd it seems that this will always fail to create the Image from the CoreGraphics.

CoreGraphics.CGWindowListCreateImage() failed.

Otherwise it works as long as it’s being executed as the user, or even executing sudo on the python script works fine.

Am i missing something with System context and CoreGraphics API’s ?

[BoboTiG]

I do not have a macOS machine anymore. If someone wants to give a hand, that would be great 😃

[ishandutta2007]

Same error whenever I run it from cron. Works fine when triggered explicitly from terminal