why isn't "Modified" date updated?

[Dan Lester]

Excuse me if this has been discussed elsewhere. I find it puzzling that, on one machine, after I SuperDuper clone to a disk partition and it completes successfully, when I do "Get Info" on that partition, the "Modified" date is unchanged. Of course, if I command a clone manually, I can always go to the log and verify that it has completed successfully, but I find this a bit odd. Surely that partition has been modified by SuperDuper.

Somewhat strangely, the "Modified" date is changed properly on another. Same version of SuperDuper, but different OS's. I have to suspect this is an OS issue and not a SuperDuper issue, but ...?

[dnanian]

The "Modified Date" is not part of the files in the file system, and thus isn't updated when those files are copied...and the system doesn't track changes to the file system and update the modified date. So... it's just the way the file system works, Dan.

If you want to keep track of when the copy was made, you can use an "after-copy" shell script to touch a file at the top of the drive (for example). Of course, that means the copy isn't "unchanged" from the source, but one file there won't make a difference...

[Dan Lester]

Thank you, Dave. As I thought, this probably wasn't even a SuperDuper issue. But it is a little strange that on one machine, with one OS, that "Modified Date" is updated after a clone, but on another it is not.