Re: Msdos name alias patch for 2.1.48

Linus Torvalds (
Thu, 7 Aug 1997 12:09:03 -0700 (PDT)

On Thu, 7 Aug 1997, Ingo Molnar wrote:
> so either we break this model (no way!), or we force MSDOSFS (users ;) to
> fit the semantics of Linux. Fortunately there are almost no applications
> that rely on exact MSDOS lookup semantics, apart from things that see
> MSDOS created physical file archives directly (unzip, rar, arj, tar), or
> cross-filesystem tools (cp -R, cpio, tar). The following libc hack i think
> provides a working migration path:
> - MSDOSFS is 'nonescaping', names leading into MSDOSFS can never leave
> - kernel returns -ENONCANONIC from real_lookup(msdos_lookup()) if
> the name is noncanonic

Ugh. The error code I could live with, but libc then mangling the name and
re-trying I definitely don't like.

I guess we'll just have to come up with some other solution than forcing
"canonicalness". It's just that every non-canonical solution seems to
imply undue complications on the VFS layer that are losses overall and
only make sense for msdos-fs.