actions and curl

Hello,
I’m trying to add action which uses curl functions which would be called when someone comment a post.

It’s look like:

function my_func() {
   $url = 'https://something/file.php';
   $c = curl_init($url);
   if( $c ) {
      /* doing something */
      curl_close($c);
   }
}

add_action('comment_post', 'my_func');

This usage doesn’t work at all – I have a blank page after making new comment on the blog. I’ve checked that it crashes when I call curl_init(). Does anyone have some similar problems?