Bug 12307

There is no way to tell whether an asynchronous XML HTTP request to the local disk (when running a page from file:///) has failed. // #1 works ok from HTTP var r = new XMLHttpRequest(); r.open("GET", "http://www.apple.com/nowhere.html", true); r.send(); // wait ... r.status == 404 // #2 works ok synchronously var r = new XMLHttpRequest(); r.open("GET", "nowhere.html", false); r.send(); // throws an error  // #3 but asynchronously ... no way to detect the error var r = new XMLHttpRequest(); r.open("GET", "nowhere.html", true); r.send(); // wait ... no error thrown r.status == 0 Both Internet Explorer and Firefox seem to ignore async when requesting a resource from the local disk. They both throw an exception like Safari does in the second example. But they also both throw an exception in the third example whereas Safari doesn't.