Mapped network drive 'IN_CLOSE_WRITE' events for .eml files

[Dominic R]

I'm trying OneCommander v.3.104.1.0 under Windows 25H2. I notice that when listing '.eml' files on a mapped network drive (server is running Samba under Linux) it triggers 'IN_CLOSE_WRITE' events for them  (these are email files normally opened using Thunderbird).

This is even though I have turned off 'Show metadata on network files'.

I realise that OneCommander must read the files to show the preview (and that is very helpful!), but it doesn't need to open them with write permissions, why is it doing that? I don't see the same behaviour for other filetypes (.pdf, .xlsx etc) even though these also show previews. The previewer for '.eml' files shows a fairly simple preview in a monospace font, I guess it is something internal as I never saw that layout before (in Thunderbird or in Windows File Explorer). In any case the 'IN_CLOSE_WRITE' events happen with any '.eml' files when they appear in the listing, before they are previewed or even if they are never previewed.

I feel OneCommander is 'exceeding its authority' by opening these files with write permission (even though it does not make any changes to them) and for reasons that are specific to my setup it causes significant extra load on the server. Is there a way to stop OneCommander doing this please?

[OneCommander Support]

I'll have to check. It should be already opening them with read by default

https://github.com/Sicos1977/MSGReader/blob/8497c73b7d4b95ae238d33c5725c0e9920c8df98/MsgReader/Mime/Message.cs#L675