https://youtube-dl.org/downloads/latest/youtube-dl-2020.11.1...
$ curl -sS -D- -o/dev/null \
https://youtube-dl.org/downloads\
/latest/youtube-dl-2020.11.12.tar.gz
HTTP/1.1 302 Found
Date: Mon, 16 Nov 2020 15:04:10 GMT
Server: Apache/2.2.15 (CentOS)
Location: https://youtube-dl.org/downloads\
/2020.11.12/youtube-dl-2020.11.12.tar.gz
Content-Length: 3
Connection: close
Content-Type: text/html; charset=iso-8859-1
$ curl -sS -D- -o/dev/null \
https://youtube-dl.org/downloads/\
2020.11.12/youtube-dl-2020.11.12.tar.gz
HTTP/1.1 302 Found
Date: Mon, 16 Nov 2020 15:05:03 GMT
Server: Apache/2.2.15 (CentOS)
Location: https://gitlab.com/dstftw/\
youtube-dl/uploads/99d745f22ca3c2a8e9a2\
3def5446289a/youtube-dl-2020.11.12.tar.gz
Content-Length: 3
Connection: close
Content-Type: text/html; charset=iso-8859-1 (base) /tmp curl -sS -D- -o/dev/null https://youtube-dl.org/downloads/latest/youtube-dl-2020.11.12.tar.gz
HTTP/1.1 302 Found
Date: Mon, 16 Nov 2020 15:52:13 GMT
Server: Apache/2.2.15 (CentOS)
Location: https://youtube-dl.org/downloads/2020.11.12/youtube-dl-2020.11.12.tar.gz
Content-Length: 3
Connection: close
Content-Type: text/html; charset=iso-8859-1
(base) /tmp curl -sS -D- -o/dev/null https://youtube-dl.org/downloads/2020.11.12/youtube-dl-2020.11.12.tar.gz
HTTP/1.1 302 Found
Date: Mon, 16 Nov 2020 15:52:27 GMT
Server: Apache/2.2.15 (CentOS)
Location: https://github.com/ytdl-org/youtube-dl/releases/download/2020.11.12/youtube-dl-2020.11.12.tar.gz
Content-Length: 3
Connection: close
Content-Type: text/html; charset=iso-8859-1 $ curl -I https://youtube-dl.org/downloads/latest/youtube-dl-2020.11.12.tar.gz
HTTP/1.1 302 Found
Date: Mon, 16 Nov 2020 19:10:37 GMT
Server: Apache/2.2.15 (CentOS)
Location: https://youtube-dl.org/downloads/2020.11.12/youtube-dl-2020.11.12.tar.gz
Connection: close
Content-Type: text/html; charset=iso-8859-1 $ curl -sS -v -I \
https://www.jefftk.com 2>&1 | grep '^>'
> HEAD / HTTP/1.1
> Host: www.jefftk.com
> User-Agent: curl/7.58.0
> Accept: */*
$ curl -sS -v -D- -o/dev/null \
https://www.jefftk.com 2>&1 | grep '^>'
> GET / HTTP/1.1
> Host: www.jefftk.com
> User-Agent: curl/7.58.0
> Accept: */*
>
It turns out that, often enough to be worth worrying about, servers do not return the same headers in response to a HEAD request as a GET request, so I always send a GET request when debugging strange behavior.