sed - 如何使用 netcat 仅请求网页标题？

Question

我不确定 netcat 是否有一些用于请求 http 标头的命令，还是应该使用 sed 来过滤结果？如果在这种情况下使用 sed，是不是我只需要在第一个“<”出现之前提取所有内容？

Answer 1

The command line tool curl has the -I option which only gets the headers:

-I/--head

(HTTP/FTP/FILE) Fetch the HTTP-header only! HTTP-servers feature the command HEAD which this uses to get nothing but the header of a document. When used on a FTP or FILE file, curl displays the file size and last modification time only.

Demo:

$ curl -I stackoverflow.co.uk
HTTP/1.1 200 OK
Cache-Control: private
Content-Length: 503
Content-Type: text/html; charset=utf-8
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Date: Thu, 26 Sep 2013 21:06:15 GMT