jquery ajax outputting success status

I'm using a basic ajax function with on success having

success: function(html){
jQuery("#output").html(html);
}

the callback is always successful giving me either 0 or -1 at the end of my returned开发者_如何学Python html. What is causing this?

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Answer to your question is very simple.

The url to which the ajax is called is either returning output 0 or -1 depending on the data sent to that page