When the code following the await can be executed on any thread, it's
recommended to use ConfigureAwait(false) to avoid unnecessary context
switching and potential deadlocks.
If one of these fields is accidentally reassigned, it's possible for
threads to be oblivious to an existing lock. By making the fields
readonly, we will be notified at compile-time if we inadvertently
redefine one of these fields.
This is inspired largely by the new (/ returning) feature of OneDrive in Windows 10 Fall Creator's Update, which downloads files on-demand.
A side effect of that change is that the OneDrive folder (and subfolders of it) are marked as reparse points, even though they are not technically standard symlinks.
With this change, a new extension method IsSymlink is added for ISnapshotService and ISystemIO, which checks both the file attributes (for reparse point) and the symlink target path (if null, the path is not treated as a symlink).
All places that previously checked only the file attributes have been updated to use either this method (or at least the same logic, in the case of the core BackupHandler file check).
One side effect of this change is that '--symlink-policy=store' no longer ignores empty symlinks - they are now treated as regular files.
If there are empty symlinks, they will now be backed up as if they were regular files, but I don't know what the conditions are that create symlinks like that, so this might not effect anything in practice.
InvariantCulture is useful when comparing / sorting human language strings in a culturely correct way. It handles things like accented letters in a way that makes sense to humans (e.g., 'a' should be sorted next to 'á', rather than after 'z').
Ordinal looks just at the raw code points of the characters. As such, it is recommended for use in cases when comparing system strings (file paths, command line parameters, config settings, etc.). Since it doesn't need to use the culture specific sorting rules, this method can often be faster.
For more information, see https://stackoverflow.com/questions/492799/difference-between-invariantculture-and-ordinal-string-comparison (and other related questions)
Also added support for restoring from an exported configuration file, by loading the values into the restore-direct view.
This adds support for importing a configuration file stored on a remote destination as mentioned in #2282.
This fixes#2321
This fixes#1311
Kenneth Hsu