Question

我在c中创建了一个简单的客户端套接字，但这个套接字大部分都是成功的。

我遇到的问题是我的客户端套接字获得301状态，具有讽刺意味的是，www.w3.org。

观察，当我使用客户端c套接字发送以下GET时

GET / HTTP/1.1
Host: time.com
Connection: keep-alive
Accept: */*
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2490.80 Safari/537.36
Accept-Encoding: gzip, deflate, sdch
Accept-Language: en-US,en;q=0.8

我收到了

HTTP/1.1 200 OK
Server: nginx
Date: Thu, 12 Nov 2015 08:44:34 GMT
Content-Type: text/html; charset=UTF-8
Transfer-Encoding: chunked
Connection: keep-alive
Vary: Accept-Encoding
Last-Modified: Thu, 12 Nov 2015 08:40:48 GMT
Cache-Control: max-age=74, must-revalidate
X-nananana: Batcache
Vary: Cookie
X-hacker: If you're reading this, you should visit automattic.com/jobs and apply to join the fun, mention this header.
X-Pingback: http://time.com/xmlrpc.php
X-UA-Compatible: IE=edge,chrome=1
Link: <http://ti.me/nACNOw>; rel=shortlink
Content-Encoding: gzip
X-ac: 4.ord _dca

但是，当我向www.w3.org发送GET请求时。

GET / HTTP/1.1
Host: www.w3.org
Connection: keep-alive
Accept: */*
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2490.80 Safari/537.36
Accept-Encoding: gzip, deflate, sdch
Accept-Language: en-US,en;q=0.8

我收到了

HTTP/1.1 301 Moved Permanently
Content-length: 0
Location: http://www.w3.org/
Connection: close

当谷歌浏览器向www.w3.org发送类似的GET时

GET / HTTP/1.1
Host: www.w3.org
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
Accept-Encoding: gzip, deflate, sdch
Accept-Language: en-US,en;q=0.8
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2490.86 Safari/537.36

服务器以

响应

HTTP/1.1 200 OK
Accept-Ranges: bytes
Cache-Control: max-age=600
Content-Length: 39276
Content-Location: Home.html
Content-Type: text/html; charset=utf-8
Date: Sun, 15 Nov 2015 04:40:47 GMT
ETag: "996c-524790d293380;89-3f26bd17a2f00"
Expires: Sun, 15 Nov 2015 04:50:47 GMT
Last-Modified: Sat, 14 Nov 2015 05:00:14 GMT
P3P: policyref="http://www.w3.org/2014/08/p3p.xml"
Server: Apache/2
TCN: choice
Vary: negotiate,accept

为什么我的客户的GET虽然与Chrome的GET几乎等同，却收到了301？

某些网站是否有一组严格的必需HTTP标头字段？

我错过了一幅更大的画面吗？

Answer 1

w3.org使用永久重定向强制规范网址www.w3.org。仅请求w3.org将导致HTTP 301.规范URL是首选项，因此不应假定未加前缀的URL将始终重定向到www前缀的URL。

尽管主机名正确，服务器响应标头仍会显示状态码301

1 个答案: