cURLを使用してリダイレクトURLを取得する

使用curl -L。マニュアルから：

   -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  authentica-
          tion  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.