pub fn validate_single_root(path: &str) -> Result<PathBuf, (u8, String)>Expand description
Validate and canonicalize an FS_SYNC_SINGLE root: the same
canonicalization as validate_root, plus the path must not be a
directory — a directory root answers the existing invalid-path error
(docs/design/fs-watch.md “Single-file sync”). Canonicalization resolves
symlinks, so the returned path is the file itself, never a link to it.