(PHP 4 >= 4.0.2, PHP 5, PHP 7)
get_resource_type — Returns the resource type
$handle
   )This function gets the type of the given resource.
handleThe evaluated resource handle.
   If the given handle is a resource, this function
   will return a string representing its type. If the type is not identified
   by this function, the return value will be the string 
   Unknown.
  
   This function will return FALSE and generate an error if 
   handle is not a resource.
  
Example #1 get_resource_type() example
<?php
// prints: mysql link
$c = mysql_connect();
echo get_resource_type($c) . "\n";
// prints: stream
$fp = fopen("foo", "w");
echo get_resource_type($fp) . "\n";
// prints: domxml document
$doc = new_xmldoc("1.0");
echo get_resource_type($doc->doc) . "\n";
?>