nodejs: Where is image upload stored?

I did a tutorial for nodejs image upload.

Question: Where does nodejs store the uploaded image?

I work locally mit localhost:8888 (I'm new to nodejs and programing)

requestHandler.upload = function( response, request ) {
console.log( "Request for 'upload' is called." );

var form    = new formidable.IncomingForm();

console.log( "Preparing upload" );


form.parse( request, function( error, fields, files ){
    console.log( "Completed Parsing" );

    if( error ){
        response.writeHead( 500, { "Content-Type" : "text/plain" } );
        response.end( "CRAP! " + error + "\n" );
        return;
    }
console.log("the path is: " +files.upload.path);

    fs.renameSync( files.upload.path, "/tmp/" + files.upload.name );

    response.writeHead( 200, { "Content-Type" : "text/html" } );
    response.write( "received image <br />" );
    response.end( "<img src='/show?i=" + files.upload.name + "' />" );

   });
};