`file-name-buffer-file-type-alist', and whether the file exists:
If it matches in `untranslated-filesystem-list':
- If the file exists: `no-conversion'
- If the file does not exist: `undecided'
+ If the file exists: `undecided'
+ If the file does not exist: `undecided-unix'
If it matches in `file-name-buffer-file-type-alist':
If the match is t (for binary): `no-conversion'
If the match is nil (for dos-text): `undecided-dos'