Function library_key 

pub fn library_key(root: &Path) -> String

The key naming a library’s actions file: Eagle’s metadata.json carries no library id, so it is the 64-bit FNV-1a hash of the library’s canonical path (symlinks resolved, no trailing slash) as 16 lowercase hex digits. A path that can’t be resolved (the library is gone) is hashed as given. Moving or renaming a library therefore starts it with no actions.