demo:/root# curl -i baidu.com HTTP/1.1 200 OK Date: Wed, 27 Jul 2016 08:50:03 GMT Content-Type: text/html; charset=utf-8 Transfer-Encoding: chunked Connection: Keep-Alive Vary: Accept-Encoding Set-Cookie: BAIDUID=0012CCC7FDB7C71CCFD7564DF73CCCAA:FG=1; expires=Thu, 31-Dec-37 23:55:55 GMT; max-age=2147483647; path=/; domain=.baidu.com Set-Cookie: BIDUPSID=0012CCC7FDB7C71CCFD7564DF73CCCAA; expires=Thu, 31-Dec-37 23:55:55 GMT; max-age=2147483647; path=/; domain=.baidu.com Set-Cookie: PSTM=1469609403; expires=Thu, 31-Dec-37 23:55:55 GMT; max-age=2147483647; path=/; domain=.baidu.com Set-Cookie: BDSVRTM=0; path=/ Set-Cookie: BD_HOME=0; path=/ Set-Cookie: H_PS_PSSID=1446_18240_20416_19861_15954_11956_20705_20696; path=/; domain=.baidu.com P3P: CP=" OTI DSP COR IVA OUR IND COM " Cache-Control: private Cxy_all: baidu+938d6eaf9bc28d04fd2b7d2ebd708c74 Expires: Wed, 27 Jul 2016 08:49:57 GMT X-Powered-By: HPHP Server: BWS/1.1 X-UA-Compatible: IE=Edge,chrome=1 BDPAGETYPE: 1 head($url) Get document headers. Returns the following 5 values if successful: ($content_type, $document_length, $modified_time, $expires, $server) Returns an empty list if it fails. In scalar context returns TRUE if successful. 得到document headers. 返回下面5个值如果成功的话 ($content_type, $document_length, $modified_time, $expires, $server) [root@dr-mysql01 0727]# cat a1.pl use LWP::Simple; my $host='http://www.baidu.com'; ($content_type, $document_length, $modified_time, $expires, $server)= head($host); print "$content_type is $content_type "; print "$document_length is $document_length "; print "$modified_time is $modified_time "; print "$expires is $expires "; print "$server is $server "; [root@dr-mysql01 0727]# perl a1.pl $content_type is text/html $document_length is 277 $modified_time is 1465786250 $expires is $server is bfe/1.0.8.14