Bug in "Synchronize directories" when comparing timestamps

[chaos7]

Steps to repro:
1. Create two folders with identical files
2. Select one file, go to "change attributes" and change the timestamp by 1, 2 or 3 seconds
3. Open "Synchronize directories", uncheck "ignore date", and click Compare.

Expected: the two files should be shown as different
Actual: files with timestamps that are 1, 2 or 3 seconds apart are shown as identical, even though "ignore date" is unchecked.

Image: https://i.snipboard.io/N04xpv.jpg

[white]

Moderator message from: white » 2025-11-02, 00:32 UTC

Moved topic
» from Total Commander (English) to TC11.x bug reports (English)

[ghisler(Author)]

This is intentional. Differences of 1 to 3 seconds often occur when copying files with odd seconds from an NTFS formatted drive to a FAT32 drive, because FAT32 timestamps only support even times (2 second resolution). When you copy them back, they keep the even time, so checking for the file system doesn't help here.

[white]

Perhaps add something to the help page?

Suggestion in green:

ignore date

If this option is not selected, files are additionally compared by timestamp. Differences of 1–3 seconds in timestamps are ignored to account for rounding when copying between NTFS and FAT32 file systems.
If this option is selected, files with same size and name are considered identical. If additionally the option "by content" is selected, files with the same size are also compared by content. The result of such a comparison only yields to the result 'equal' or 'not equal' - the copy direction needs to be set by the user. A modification of this option makes a new comparison necessary.

[chaos7]

I see. That makes sense. It took me by surprise when I was working with photos and timestamps based on exif data where several files I was comparing were showing as identical despite small differences in their timestamps.