Still seeking advice

In performing some further research into the matter I realized that I was trying to write a file that didn’t exist. Here is the new code that works great, but I still need some assistance in appending the written file. I’ve tried all variations of the fopen() (e.g. a,a+, w, etc…) I do not want my inventory to get bloated, so when a person checks the inventory I need the xml file written over with a fresh ‘check of the inventory’.

   $path = "/cdmapi/dlapi.asmx/DLAPI?Request=retail_inv&DealerID=4229&LoginID=lrsa&[email protected]";
   $port = 80;
   $host = "";
   if (count($argv) > 1) $path = $argv[1];
   if (count($argv) > 2) $port = $argv[2];
   if (count($argv) > 3) $host = $argv[3];
   $address = gethostbyname($host);
   $socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
   socket_connect($socket, $address, $port);
   $in = "GET $path HTTP/1.0

   socket_write($socket, $in, strlen($in));
   while ($data = socket_read($socket, 2048)) {
      //echo $out;
  $file = "inventory.xml";
  $content = $data;
  if (is_writable($file)){
   if (!$handle = fopen($file, 'a')){
    echo "Cannot open file ($file)";
   if (fwrite($handle, $content) === FALSE) {
    echo "Cannot write to ($file)";
   echo "Success, wrote ($content) to file ($file)";
  } else {
   echo "the file $file is not writable";