PHP: Want fsockopen to retrieve portion only of remote xml file.

Question

I need to retrieve a small amount of data from a very large remote XML file that I access via http. I only need a portion of the file at the beginning, but the files I am accessing can often be so large that downloading them all will cause a timeout. It seems like it should be possible with fsockopen to pull only as much as needed before closing the connection, but nothing I have tried has worked.

Below is a simplified version of what I have been trying. Can anyone tell me what I need to do differently?

<?php

 $k = 0;

 function socketopen($funcsite, $funcheader){

 $fp = fsockopen ($funcsite, 80, $errno, $errstr, 5);

 $buffer = NULL;

 if ($fp) {

    fwrite($fp, "GET " . $funcheader . " HTTP/1.0\r\nHost: " . $funcsite. "\r\n\r\n");


 while (!feof($fp)) {
    $buffer = fgets($fp, 4096);
    echo $buffer;

    if($k == 200){
        break;
    }
    $k++;
  }

    fclose ($fp);
  } else {
    print "No Response:";
 }
 return ( html_entity_decode($buffer));
}

$site = "www.remotesite.com";
$header = "/bigdatafile.xml";
$data = socketopen($site, $header);
?>

This works fine, but always opens and downloads the entire remote file. (I actually use a different conditional than the if($k = x), but that shouldn't matter).

Any help greatly appreciated. -Jim

Answer 1

with this code you could download the entire rss

  if (!$xml = simplexml_load_file("http://remotesite.com/bigrss.rss))
    {
       throw new RuntimeException('Unable to load or parse  feed');
    }

  else
  {
    file_put_contents($xml,'mybigrss.rss'); 
  }

but if you want to get just some parts then do the following;

$limit = 512000; // set here a limit 
$sourceData = fread($s_handle,$limit); 

// your code ect..

Or with eof

$source='';
while (!feof($s_handle))
$source.=fread($s_handle,1024); // set limit 

Answer 2

Any reason not to use file_get_contents() instead?

$buffer = html_entity_decode(file_get_contents('http://www.remotesite.com/bigdatafile.xml', 0, null, $offsetBytes, $maxlenBytes));

You just need to specify $offsetBytes and $maxlenBytes.

---

Try this:

set_time_limit(0);

echo $buffer = html_entity_decode(file_get_contents('http://www.remotesite.com/bigdatafile.xml', 0, null, 1024, 4096));