I was testing mounting and reading data from a .obb file and everything worked fine. I then wanted to test downloading the .obb file from google play, so I used monitor to remove the .obb file from my device, not thinking that the file was still mounted at /mnt/obb/!
So I put the .obb file back, and StorageManager.isObbMounted() always returns true, but when I examine the directory (using a File object created with StorageManager.getMountedObbPath()), it's always empty.
I think the mount point is corrupted because I removed the .obb file while it was mounted. I'd like to 'umount /mnt/obb/' to get back to a clean state, but I always get 'failed: Operation not permitted'.
How can I clean up the mess I made?
Thanks!
Rebooting the device fixed the issue.