Uploading and downloading

Uploading

Drag files onto the window, or press ⌘U.

Files over 100 MB are uploaded in parallel parts. If the transfer is interrupted, Bucketree can pick it up again from the parts B2 already holds: open the bucket and the abandoned-uploads banner offers Resume.

Folders are not uploaded yet. A partial upload of a folder would be worse than refusing, so Bucketree refuses.

Downloading

Select files and press ⌘D, or double-click a single file.

Downloads stream to disk rather than being held in memory, so file size is not a limit.

Checksums

Every upload carries a SHA1 that B2 checks on arrival, and large files carry a whole-file SHA1 as well. Every download is verified against it.

The distinction Bucketree draws, which matters: a download is reported as verified, or as not verified and why. It is never reported as fine when nothing was checked. A file uploaded by another tool may carry no whole-file checksum at all, in which case Bucketree says so rather than implying success.

The Checksum column in the listing shows whether a file can be verified at all. Get Info shows the value and which of the two it is.

Whole-file checksums on upload

Recording a whole-file SHA1 means reading the file once before the upload starts. On a large file that is not free: about a minute for five gigabytes, limited by your disk rather than by the hashing.

It is on by default and can be turned off in Settings. B2 has no way to add it afterwards, so it is that one read or nothing.