>You should not deal with the decomposition of file names in clisp.
The devil lies in the details. For instance, there's a bug which I've not
chased down in the area of ssh, fuse-ssh(on Linux), Emacs and readline.
Somewhere, when logging remotely from Linux into MacOS, or when
copying files via fuse-ssh (on Linux) to MacOS, bash's readline got confused by
Umlauts like äöü. It appears that for some files they were decomposed,
for others not. As a consequence, completion and backspace behaved oddly.
The Finder showed all of them alike, but IIRC Emacs
noticed a difference (or was it the terminal that did not display everything
as expected?). I'm sorry I don't remember the details. (MacOS 10.5.8)
Preliminary conclusion: decomposition is not transparent to the app...
>I believe that it does not occur on NFS or SMB/CIFS mounts.
The Mac documentation that Pascal recently linked to says
NFS: don't know, not specified [I guess it depends on the host];
SMB: no decomposition.
>For example, by forcing *PATHNAME-ENCODING* to be UTF-8 on MacOS X.
This sounds very reasonable.