On 9/15/25 06:26, Pádraig Brady wrote:
I think there is little point in restricting characters unless it's done
completely,
because if not then you have to deal with the issue anyway.
So if the restriction is done, it should be done at a low level,
perhaps as a kernel option or something.
Which Linus explicitly rejected 20 years ago because you can always
insert a usb stick (or mount a loopback image, or mount a network
filesystem) made on a system that supports the full range of characters.
Even just a historical one from your own system before you broke it.
The only two illegal characters in Linux VFS filenames are / and NULL,
and the kernel preserves and does not interpret everything else, I.E.
filenames are bytestreams, period. That's explicit policy.
This has always made supporting case insensitive filesystems a pain on
Linux, and Linus repeated just recently that he doesn't care:
https://www.osnews.com/story/142205/torvalds-states-the-obvious-file-systems-should-be-case-sensitive/
Perhaps even a translation layer
in the kernel/libc to support older existing files with problematic
characters,
while disallowing new files with those chars.
Doing this higher up in user space would only be playing
whac-a-mole with the issue I think.
This is not a new issue, and Posix being stupid is nothing new.
Feel free to break The Hurd, I guess?
Rob
