C++ 获取从.exe文件到xulrunner的返回值

我有一个.exe MFC文件，我想用xulrunner调用它。我使用from launch命令，但无法从.exe文件返回值

有人能帮我怎么做吗

    var file = Components.classes["@mozilla.org/file/local;1"]
        .createInstance(Components.interfaces.nsILocalFile);

    var filePath =Components.classes["@mozilla.org/file/directory_service;1"]
            .getService(Components.interfaces.nsIProperties)
            .get("AChrom", Components.interfaces.nsIFile).parent;

    file.initWithPath("file.exe");
    file.launch();

---

如果要返回值，请使用“nsIProcess”：

var file = Components.classes["@mozilla.org/file/local;1"]
                     .createInstance(Components.interfaces.nsIFile);
file.initWithPath("c:\\myapp.exe");
var process = Components.classes["@mozilla.org/process/util;1"]
                        .createInstance(Components.interfaces.nsIProcess);
process.init(file);
var args = ["argument1", "argument2"];
process.run(true, args, args.length);
var retVal=process.exitValue;