javascript - jquery - return ajax response value

This may sound silly, but I'm stuck trying to get the value from an ajax response.

I have a dummy.php file which just echoes "hello world" and I'm making an ajax request to get the text and console.log it.

My code is:

$(function(){
    console.log( getResponse() );
})
function getResponse(){
var request = $.ajax({
    url: "dummy.php",
    type: "POST"
});
request.success(function(data, textStatus, jqXHR){
    // part i'm missing
});
return return_value_from_the_dummy_file;
}

And I want the getResponse function to return the response text or in case of an error some text I'll set later.

What should I do?