run docker failure

[xinmans]

sudo docker run -d -p 7774:7771 mosajjal/pproxy:latest -l http://:7771 -r socks5://192.168.3.4:8081 -vv

error as below, what's wrong?
Traceback (most recent call last):
File "/usr/local/lib/python3.9/asyncio/selector_events.py", line 261, in _add_reader
key = self._selector.get_key(fd)
File "/usr/local/lib/python3.9/selectors.py", line 193, in get_key
raise KeyError("{!r} is not registered".format(fileobj)) from None
KeyError: "<_io.TextIOWrapper name='' mode='r' encoding='utf-8'> is not registered"
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/usr/local/bin/pproxy", line 8, in
sys.exit(main())
File "/usr/local/lib/python3.9/site-packages/pproxy/server.py", line 943, in main
verbose.setup(loop, args)
File "/usr/local/lib/python3.9/site-packages/pproxy/verbose.py", line 67, in setup
loop.add_reader(sys.stdin, functools.partial(all_stat_other, args.stats))
File "/usr/local/lib/python3.9/asyncio/selector_events.py", line 336, in add_reader
self._add_reader(fd, callback, *args)
File "/usr/local/lib/python3.9/asyncio/selector_events.py", line 263, in _add_reader
self._selector.register(fd, selectors.EVENT_READ,
File "/usr/local/lib/python3.9/selectors.py", line 360, in register
self._selector.register(key.fd, poller_events)

[kng]

Looked like the same for me, the solution is to add -i, like docker run -p 8080:8080 -di mosajjal/pproxy:latest -vv