docs: def symlink(source, destination, adapter=None, must_exist=True, fatal=True, logger=LOG.debug):
      """
      Symlink source <- destination
  
      :param str|None source: Source file or folder
      :param str|None destination: Destination file or folder
      :param callable adapter: Optional function to call on 'source' before copy
      :param bool must_exist: If True, verify that source does indeed exist
      :param bool|None fatal: Abort execution on failure if True
      :param callable|None logger: Logger to use
      :return int: 1 if effectively done, 0 if no-op, -1 on failure
      """
      return _file_op(source, destination, _symlink, adapter, fatal, logger, must_exist=must_exist)