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On a headless Mac Mini running Mojave, my 1tb Macintosh HD is nearly full at 861gb used (after deleting some stuff - it was critical before). However the sizes of the folders within it after forcing finder to calculate their individual sizes only add up to about 100gb. The grey 'system' bar on the about my mac storage tab is over 700gb.
sudo du -sh * run in /Volumes/Macintosh HD throws too many permission denied errors to help me find the culprit.
On a PC I'd just run TreeSize and that would show me where the offending file or files were. Does anyone know of a method or tool (that doesn't cost the world, there isn't much budget for this) that'll let me track down what's eating up all the HD space?