file name changes

[rogdias]

One feature that as far as I know no sync software has is to sync file names, when the files are otherwise identical. This happens when you just change file names, usually music or photo files, and you don't want to copy them as it would be a waste of time. As long as ffs already have a way to check if two files are equal, it could detect that just the names have changed, and update them in one chosen direction.
I've been looking for a sync sw that would do this, and haven't fond this even among commercial ones.

[Zenju]

FreeFileSync checks if two files are equal by comparing their content directly. This is the most efficient way to compare files.
When you want to find files that are equal from a group of files, you would need to make checksums for each file. That's no problem so far.

But I don't really see this fitting into the design of a sync-tool The functionality you're looking for is to find duplicates. It's kind of unrelated to synchronization.

-Zenju

[sbeller]

FreeFileSync checks if two files are equal by comparing their content directly. This is the most efficient way to compare files.
When you want to find files that are equal from a group of files, you would need to make checksums for each file. That's no problem so far.

But I don't really see this fitting into the design of a sync-tool The functionality you're looking for is to find duplicates. It's kind of unrelated to synchronization.

-Zenju

Hi Zenju,
well, I don't completely agree that this is out of the scope of a sync tool. I often have that situation that rogdias describes as I have a new set of photos taken and need some time to sort them out. Until they are sorted out I still want them to be back-uped so I sync them with another hard drive.
During the photo processing I delete some of the photos and rename the remaining ones. It would be a really helpful feature if these changes then could be synched again with the external hard drive - instead of deleting the previous backup and having to do it again.
Maybe you could find a solution for this problem?

Best wishes - and thanks for your excellent work
Sven

[Zenju]

One feature that as far as I know no sync software has is to sync file names, when the files are otherwise identical. This happens when you just change file names, usually music or photo files, and you don't want to copy them as it would be a waste of time. As long as ffs already have a way to check if two files are equal, it could detect that just the names have changed, and update them in one chosen direction.
I've been looking for a sync sw that would do this, and haven't fond this even among commercial ones.

Hi Sven,

as far as I can see this feature request is all about performance optimization. But think about it:
Deleting some files and copying them again is a lot faster than reading all(!) files' content in order to get their checksums.

Regards, Zenju

[sbeller]

Hi Sven,

as far as I can see this feature request is all about performance optimization. But think about it:
Deleting some files and copying them again is a lot faster than reading all(!) files' content in order to get their checksums.

Regards, Zenju

Well yes, I think you may be right regarding the time it takes for the checksums to create.
And just leaning on the files size, date and time, would that be too insafe?

Thanks
Sven

[Zenju]

One feature that as far as I know no sync software has is to sync file names, when the files are otherwise identical. This happens when you just change file names, usually music or photo files, and you don't want to copy them as it would be a waste of time. As long as ffs already have a way to check if two files are equal, it could detect that just the names have changed, and update them in one chosen direction.
I've been looking for a sync sw that would do this, and haven't fond this even among commercial ones.

> leaning on the files size
One obvious optimization would be to only test those files for equality (by calculating their checksum) whose filesize is equal. But even with the minimum number of candidates (=2) reading both files content (+ some CPU time, but the bottleneck is of course file I/O) is approximately just as fast as deleting the file on target drive (constant time) + copying it from source to target. So even in the most optimistic case it's only as fast as a simple delete + copy operation.

Regards, Zenju

[rogdias]

One feature that as far as I know no sync software has is to sync file names, when the files are otherwise identical. This happens when you just change file names, usually music or photo files, and you don't want to copy them as it would be a waste of time. As long as ffs already have a way to check if two files are equal, it could detect that just the names have changed, and update them in one chosen direction.
I've been looking for a sync sw that would do this, and haven't fond this even among commercial ones.

Yes, Zenju, I think you are right.
Thanks for the attention.