pg_dump与数据库的连接失败

我正在尝试在本地计算机上使用pg_dump工具。但是，当我database_name在终端窗口中键入pg_dump时，我收到以下消息：

pg_dump: [archiver (db)] connection to database "demo" failed: 
could not connect to server: No such file or directory

收到此错误消息后，我进入了postgressql.conf文件（postgres的配置文件），并将listen_addresses设置为*。我的连接字符串如下所示：

  - Connection Settings -

 #listen_addresses = '*'        # what IP address(es) to listen on;
                # comma-separated list of addresses;
                # defaults to 'localhost'; use '*' for all
                # (change requires restart)
#port = 5432                # (change requires restart)
max_connections = 20            # (change requires restart)
# Note:  Increasing max_connections costs ~400 bytes of shared memory per
# connection slot, plus lock space (see max_locks_per_transaction).
#superuser_reserved_connections = 3 # (change requires restart)
#unix_socket_directory = ''     # (change requires restart)
#unix_socket_group = ''         # (change requires restart)
#unix_socket_permissions = 0777     # begin with 0 to use octal notation
                # (change requires restart)
#bonjour = off              # advertise server via Bonjour
                # (change requires restart)
#bonjour_name = ''          # defaults to the computer name
                # (change requires restart)

然后，我重新启动了计算机，希望当我pg_dump在控制台中键入内容时，会发生一些不同的事情。但是，即使重新启动后，我仍然收到无法连接服务器的错误消息（如上所述）。

接下来，我应该尝试哪些步骤来解决此问题？

先感谢您