'Mirror' can be expressed both via 'differences' and via 'changes',īut doesn't need a database file in the first case. If it wasn't for the requirement of sync.ffs_db files: One might be tempted to go further and assume 'changes' is the moreįundamental concept, and get rid of the old 'differences' categories altogether. ( create, update, delete) similarly to how it is possible with the 'differences' categories.Īll three, 'Two way', 'Mirror', and 'Update' can be expressed in these new terms. Specific decisions can be made for each individual change The last sync, in the exact same way that 'Two way' operates: by using a database file.īut FreeFileSync doesn't stop there. The solution: The new 'Update' variant will determine sync directions based on 'changes' compared to

This change couldn't be detected without a database, andĪ duplicate file was copied to the backup location instead of renaming the existing one. Unfortunately this is exactly what the old differences-based 'Update' did.Īdditionally, when a file on the source side was renamed, Them copied over again during the next sync: The user is cleaning up unwanted photos. On the other hand, deleting photos from the backup, should not get The user is making free space for new photos. When photos on the smartphoneĪre deleted, they should not also be deleted on the backup drive: These two cases, however, should get different treatment!Ĭopying photos from a smartphone to some backup location. The 'Update' synchronization variant wasn't as fundamental and useful as the other two, 'Two way', and 'Mirror'.īased on 'differences', it was unable to distinguish whetherĪ new file was created on the source, or if an old file was deleted on the target. In addition to 'differences' it is now possible to set sync directions based on 'changes': Previously they were based on the 'differences' found after comparison: left only, right only, left newer, right newer. FreeFileSync 13 generalizes the way sync directions are set up:

FreeFileSync 12.5 free instals