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MacOS may lose data on APFS-formatted disk images

bombich.com

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Re: MacOS may lose data on APFS-formatted disk images

#193

> To prevent errors when a filesystem inside of a sparse image has more free space than the volume holding the sparse image, HFS+ volumes inside sparse images will report an amount of free space slightly less than the amount of free space on the volume on which image resides. Can anyone explain the "slightly less than" part of this? Why wouldn't it just be "equal to"?

The sentences following that statement in the hdiutil manual are also helpful:

"The image filesystem currently only behaves this way as a result of a direct attach action and will not behave this way if, for example, the filesystem is unmounted and remounted. Moving the image file to a different volume with sufficient free space will allow the image's filesystem to grow to its full size."

hdiutil has some of the best man pages I've ever run across.

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