HTTP_USER_AGENT, HTTP_REFERER, HTTP_COOKIE, HTTP_HOST, HTTP_ACCEPT;
connection & request: REMOTE_ADDR, QUERY_STRING...域名;
HTTP_ACCEPT 客户端的浏览器支持的MIME类型;
REMOTE_ADDR 客户端的IP地址
QUERY_STRING... %{HTTP_HOST} www.a.com [NC,OR]
RewriteCond %{HTTP_HOST} www.b.com [NC,OR]
RewriteCond...id=$2 [L,R=301]
#判断是否使用移动端访问网站,移动端访问跳转至m.abc.com
RewriteEngine on
RewriteCond %{HTTP_USER_AGENT} ^iPhone... [NC,OR]
RewriteCond %{HTTP_USER_AGENT} ^Android [NC,OR]
RewriteCond %{HTTP_USER_AGENT} ^WAP