Archive compresses a file/directory to a writer If the path ends with a separator, then the contents of the folder at that path are at the root level of the archive, otherwise, the root of the archive contains the folder as its only item (with contents inside).

ArchiveFile compresses a file/directory to a file See Archive() doc.

Unarchive decompresses a reader to a directory The data's size is required because the zip reader needs it.

UnarchiveFile decompresses a file to a directory See Unarchive() doc.

ProgressFunc is the type of the function called for each archive file.