Read XML from a URL in PHP with cURL

I want to read XML data from a URL in Magento.

I have three textboxes. One is for baseurl and others are for username and password respectively. when i enter these values i get url like "http://xyz.com/somefile.html?username=username&password=password"

I am using the curl method to get content of the url but nothing happens. Here is my code

$url='myurl'; 

$ch = curl_init();
$timeout = 5;
curl_setopt($ch,CURLOPT_URL,$url);
curl_setopt($ch,CURLOPT_RETURNTRANSFER,1);
curl_setopt($ch,CURLOPT_CONNECTTIMEOUT,$tim开发者_开发百科eout);
$data = curl_exec($ch);
curl_close($ch);

I think there may be some problem with url because when i run this url on browser instead of showing xml contents it asks me to open or save the xml file.

Can anyone help me with this? I can not change the url so please suggest me some code that works with this type of url.

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Get the cURL command line tool from its website and then run it like this:

curl -i "http://xyz.com/somefile.html?username=username&password=password"

That's an easy and reliable way to see what's going on at the HTTP level.

Alternatively, use Firefox with Firebug to find out what's going on.