tasks/lib/zipstream.js
function callbackOnce(err, arg) {
            var cb = callback;
            callback = null;
            if (cb) { cb(err, arg); }
        }
function callbackOnce(err, arg) {
            var cb = callback;
            callback = null;
            if (cb) { cb(err, arg); }
        }
function callbackOnce ( err , arg ) { var cb = callback ; callback = null ; if ( cb ) { cb ( err , arg ) ; } }
Helper to call back only once.
Helper to call back only once .