Is it possible to preserve mergerfs.dup count when changes occur?

[anthonyryan1]

I noticed that if I mergerfs.dup a specific directory (like ~/.config), then a program changes one of the files in that directory. One copy on disk changes, but all the others retain the old content.

Is it possible to configure mergerfs so that the duplicate count is preserved on each write? Or is this out of scope

[trapexit]

Are you saying you want mergerfs to write to all versions of the file?

I've generally considered that out of scope because it seriously increases the complexity of error handling and would be incompatible or complicated with certain features. What do you do if the files are different when opened? What do you do if a file write on one of them fails but not the others? What do you do with you use moveonenospc and run out of space on one of the branches during a write but not others? It's all fine when things work but when there is an error it becomes complicated.

I'm less opposed to it than I was but I have a bunch of other features I would rather focus on.

Note that the dup app has the ability to see there are different versions and update the others.

[anthonyryan1]

That was what I was thinking about, and dup does fix it when run again the next day. I think it might only result in a rollback to the last time the dup tool was run, so it should be okay.

Definitely not a top priority feature, but I was curious if it was currently possible.