jquery - what is return type of window.open() in Javascript -

i writing code download pdf file using window.open(). passing url path of pdf file on server.

window.open(url, name, "width=910,height=750,scrollbars=yes"); 

i want check if downloading of file successful or not. return type of window.open()?

i tried

try {   window.open(url, name, "width=910,height=750,scrollbars=yes");   alert("success"); } catch(e) {   alert("failer"); } 

when change url wrong url, shows same result success.

http://www.javascripter.net/faq/openinga.htm

the return value reference new window. can use reference later, example, close window (winref.close()), give focus window (winref.focus()) or perform other window manipulations.