@type t() :: %SFTPClient.Config{
  connect_timeout: timeout(),
  dsa_pass_phrase: nil | String.t(),
  ecdsa_pass_phrase: nil | String.t(),
  host: String.t(),
  inet: :inet | :inet6,
  key_cb: nil | {module(), term()},
  modify_algorithms: nil | Keyword.t(),
  operation_timeout: timeout(),
  password: nil | String.t(),
  port: non_neg_integer(),
  private_key_pass_phrase: nil | String.t(),
  private_key_path: nil | Path.t(),
  rsa_pass_phrase: nil | String.t(),
  sftp_vsn: integer(),
  system_dir: nil | Path.t(),
  user: String.t(),
  user_dir: nil | Path.t()
}