Solved

Get the last modified header from a web page

Posted on 2004-08-10
5
326 Views
Last Modified: 2012-06-21
How can I read the last modified header of a web page on the net?

I don't want to fetch the whole content just the header

I tried

function get_headers($host, $path = "/")
{
$fp = fsockopen ("$host", 80, &$errnr, &$errstr) or die("$errno: $errstr");
fputs($fp,"GET $path HTTP/1.0\n\n");
while (!$end)
{
$line = fgets($fp, 2048);
if (trim($line) == "")
$end = true;
else
echo $line;
}
fclose($fp);
}


but I just get 'Permission denied' errors or 'Invalid URI in request GET HTTP/1.0'

am i doing it right? is there a better way?

0
Comment
Question by:stuayre
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
  • 2
5 Comments
 
LVL 25

Expert Comment

by:Marcus Bointon
ID: 11761098
Use CURL:

http://www.php.net/manual/en/ref.curl.php

There is an example of exactly how to do this in the user notes on that page by thomas at NOSPAM dot gutschke dot com
0
 
LVL 5

Accepted Solution

by:
TheClickMaster earned 200 total points
ID: 11767200
I presume the code you pasted here works and will reuse some code

function get_headers($host, $path = "/")
{
    $data  = "HEAD ".$path." HTTP/1.0\r\n";
    $data .= "HOST: ".$host."\r\n";
    $data .= "Connection: close\r\n";
    $data .= "\r\n";

    $fp = fsockopen ("$host", 80, &$errnr, &$errstr) or die("$errno: $errstr");
    fputs($fp,$data);

    $response = "";

    while (!feof($fp))  
    {
        $line = fgets($fp, 2048);
        $response .= $line;
    }

    fclose($fp);

    //display response
    echo $response."<br><br>";

    //try to find last-modified value
    $arr = explode("\r\n", $response);
    $size=count($arr);

    $result = "";

    for($n=0;$n<$size;$n++)
    {
        if(strtolower(substr($arr[$n],0,13)) == "last-modified") $result = substr($arr[$n],15);
    }

    return $result;  
}

returns an empty string or the result
0
 
LVL 1

Author Comment

by:stuayre
ID: 11769318
Thanks TheClickMaster, How would you call the function?
0
 
LVL 5

Expert Comment

by:TheClickMaster
ID: 11769903
<?php

$result = get_headers("www.google.com","/");

echo "Google.Com Last modified: ".($result != "" ? $result : "Unknown");


?>
0
 
LVL 25

Expert Comment

by:Marcus Bointon
ID: 11791068
Bear in mind that this code will not work with any URLs that cause a redirect. That's why CURL has the CURLOPT_FOLLOWLOCATION option, and it's hard work to emulate using sockets.
0

Featured Post

Online Training Solution

Drastically shorten your training time with WalkMe's advanced online training solution that Guides your trainees to action. Forget about retraining and skyrocket knowledge retention rates.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

These days socially coordinated efforts have turned into a critical requirement for enterprises.
Password hashing is better than message digests or encryption, and you should be using it instead of message digests or encryption.  Find out why and how in this article, which supplements the original article on PHP Client Registration, Login, Logo…
Explain concepts important to validation of email addresses with regular expressions. Applies to most languages/tools that uses regular expressions. Consider email address RFCs: Look at HTML5 form input element (with type=email) regex pattern: T…
This tutorial will teach you the core code needed to finalize the addition of a watermark to your image. The viewer will use a small PHP class to learn and create a watermark.

691 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question