bug#41463: 27.0.91; ACL error on Windows when trying to save file

[Eli Zaretskii]

> From: Lars Ljung <lars@matholka.se>
> Date: Fri, 22 May 2020 19:47:39 +0200
> 
> I get the following error when trying to save a specific file:
> 
> Saving file h:/some/file.txt...
> file-extended-attributes: Getting ACLs: Input/output error, h:/some/file.txt
> 
> This is unexpected since both Emacs 26.3 and notepad.exe are able to
> write to this file. Even though I also get an error when using the
> Get-Acl command in PowerShell.

Please report all the details: the ACLs and the owner of that file,
and your user's name and group.  It is impossible to investigate this
without those details.

There was no change in handling of ACLs between Emacs 26 and 27, but
some file-related operations now signal an error instead of silently
failing.  I'm guessing you bumped into one such situation.

Thanks.