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Get the last modified header from a web page

Posted on 2004-08-10
5
312 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

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