Mac Intel build error making dmg, hdiutil cannot detach image

[Tom Goddard]

The Intel Mac build failed in making a DMG with the following error. Also failed the previous day.

Make DMG
Run python3.10 -m dmgbuild -s ./utils/build/macos/dmgbuildsettings.json "ChimeraX Installer" ChimeraX.dmg
Traceback (most recent call last):

File "/usr/local/Cellar/python@3.10/3.10.19_1/Frameworks/Python.framework/Versions/3.10/lib/python3.10/runpy.py", line 196, in _run_module_as_main

return _run_code(code, main_globals, None,

File "/usr/local/Cellar/python@3.10/3.10.19_1/Frameworks/Python.framework/Versions/3.10/lib/python3.10/runpy.py", line 86, in _run_code

exec(code, run_globals)

File "/usr/local/lib/python3.10/site-packages/dmgbuild/main.py", line 67, in <module>

main()

File "/usr/local/lib/python3.10/site-packages/dmgbuild/main.py", line 56, in main

build_dmg(

File "/usr/local/lib/python3.10/site-packages/dmgbuild/core.py", line 847, in build_dmg

raise DMGError(callback, f"Unable to detach device cleanly: {output}")

dmgbuild.core.DMGError: Unable to detach device cleanly: hdiutil: couldn't eject "disk4" - Resource busy

Error: Process completed with exit code 1.

I've been trying to get new Mac builds to collaborator Willow each day so this is annoying and embarassing to have to keep reminding him to get the Mac ARM build. Hopefully a work-around can be found to avoid this error. It seems it is some race condition where hdiutil cannot detach the image.