200 HTTP CODE at non-url strings

$agent = "Mozilla/4.0 (compatible; MSIE 5.01; Windows NT 5.0)";
$ch=curl_init();
   curl_setopt ($ch, CURLOPT_URL,$url );
   curl_setopt($ch, CURLOPT_USERAGENT, $agent);
   curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);
   curl_setopt ($ch,CURLOPT_VERBOSE,false);
   curl_setopt($ch, CURLOPT_TIMEOUT, 5);
   curl_setopt($ch,CURLOPT_SSL_VERIFYPEER, FALSE);
   curl_setopt($ch,CURLOPT_SSLVERSION,3);
   curl_setopt($ch,CURLOPT_SSL_VERIFYHOST, FALSE);
   $page=curl_exec($ch);
   //echo curl_error($ch);
   $httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
   curl_close($ch);

I'm using cUrl at my project. I'm getting HTTP CODE of web sites. But when i try "asdasd" ($url="asdasd") , returned HTTP CODE is 200 . But "asdasd" isn't a web site. Why HTTP CODE is 200 ?

You might want to check the return value from curl_exec first. It says in the manual:

Returns TRUE on success or FALSE on failure. However, if the CURLOPT_RETURNTRANSFER option is set, it will return the result on success, FALSE on failure.

For curl_getinfo there's a side note:

Information gathered by this function is kept if the handle is re-used. This means that unless a statistic is overridden internally by this function, the previous info is returned.

So that HTTP 200 might well be the result of a previous cURL invocation.