I set the port to 888 in my linux, but got "Error listening on port 8080: Error code: -9992(0x-2708), Permission denied."

[carlhung]

I set the port to 888, then i ran the websocket server in my ubuntu.
but i got this error:
[2019-07-19T01:16:43.205+08:00] [ERROR] [main.swift:24 Project1] Error listening on port 8080: Error code: -9992(0x-2708), Permission denied.