Solved

Get the last modified header from a web page

Posted on 2004-08-10
5
288 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
  • 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

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

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

Nothing in an HTTP request can be trusted, including HTTP headers and form data.  A form token is a tool that can be used to guard against request forgeries (CSRF).  This article shows an improved approach to form tokens, making it more difficult to…
Since pre-biblical times, humans have sought ways to keep secrets, and share the secrets selectively.  This article explores the ways PHP can be used to hide and encrypt information.
The viewer will learn how to look for a specific file type in a local or remote server directory using PHP.
The viewer will learn how to create and use a small PHP class to apply a watermark to an image. This video shows the viewer the setup for the PHP watermark as well as important coding language. Continue to Part 2 to learn the core code used in creat…

910 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

Need Help in Real-Time?

Connect with top rated Experts

21 Experts available now in Live!

Get 1:1 Help Now