Pobieranie tylko nagłówka odpowiedzi z POSTU HTTP za pomocą curl

-D, --dump-header <file>
       Write the protocol headers to the specified file.

       This  option  is handy to use when you want to store the headers
       that a HTTP site sends to you. Cookies from  the  headers  could
       then  be  read  in  a  second  curl  invocation by using the -b,
       --cookie option! The -c, --cookie-jar option is however a better
       way to store cookies.

I

-S, --show-error
       When used with -s, --silent, it makes curl show an error message if it fails.

I

-L/--location
      (HTTP/HTTPS) If the server reports that the requested page has moved to a different location (indicated with a Location: header and a 3XX response
      code), this option will make curl redo the request on the new place. If used together with -i/--include or -I/--head, headers from  all  requested
      pages  will  be  shown.  When authentication is used, curl only sends its credentials to the initial host. If a redirect takes curl to a different
      host, it won’t be able to intercept the user+password. See also --location-trusted on how to change this. You can limit the amount of redirects to
      follow by using the --max-redirs option.

      When curl follows a redirect and the request is not a plain GET (for example POST or PUT), it will do the following request with a GET if the HTTP
      response was 301, 302, or 303. If the response code was any other 3xx code, curl will re-send the following  request  using  the  same  unmodified
      method.

Ze strony man. więc

curl -sSL -D - www.acooke.org -o /dev/null

Śledzi przekierowania, zrzeka nagłówki na stdout i wysyła dane do /dev / null (TO JEST GET, nie POST, ale możesz zrobić to samo z postem - po prostu dodaj dowolną opcję, której już używasz do wysyłania danych)

Zwróć uwagę na - Po -D, co oznacza, że wyjściowym "plikiem" jest stdout.