Port zero no longer accepted in URLs

[bagder]

I did this

curl http://localhost:0
curl: (3) URL using bad/illegal format or missing URL

(via @bradfitz at https://twitter.com/bradfitz/status/1466474708841512960)

I expected the following

$ curl http://localhost:0
curl: (7) Failed to connect to localhost port 0 after 0 ms: Connection refused

This worked before 7.62.0. I even blogged about using port zero a while ago.

curl/libcurl version

7.80.0 and current git

operating system

independent