US Patent 12079171 Symbolic link based placeholders

Symbolic link based placeholders are used for cloud stored data synchronization. To synchronize cloud stored data, placeholders may be implemented as bidirectional symbolic links to a location that has a custom virtual file system (VFS) mounted. When a symbolic link is opened, the operating system may be directed to the custom VFS. The custom VFS may hydrate the file through a synchronization engine, and place the hydrated file at the location of the original symbolic link. The custom VFS may then redirect back to the primary file system of the operating system to allow the operation on the file to complete. Complexity and resource consumption may be reduced by passing placeholder requests instead of all requests through the custom VFS.