如何在 Firefox 插件中追加到文件？

var tabs = require("sdk/tabs");
var iofile = require("sdk/io/file");
var widgets = require("sdk/widget");
var selection = require("sdk/selection");


function console_log(text) {
    console.log(selection.text);
}

function print(text) {
    console.log(text);
}

function dir_object(object_to_parse) {
    var name = '';
    for (name in object_to_parse) {
        print(name);
    }
}

function write_text(filename, text) {
    var fh = iofile.open(filename, 'w');
    var content = fh.read();

    dir_object(fh);

    selected_text = text + "\n";
    fh.write(selected_text);
    fh.flush();
    fh.close()
}

function select_text_handler() { 
    write_text('/tmp/foo', selection.text);
}

var widget = widgets.Widget({
    id: "scribus-link",
    label: "Scribus website",
    contentURL: "http://www.mozilla.org/favicon.ico",
    onClick: function() {
    }
});



selection.on('select', function () { select_text_handler(); });

“打开”“w”中的文件，这会截断我现有的文件！如何以“附加”模式打开然后“查找”？https://addons.mozilla.org/en-US/developers/docs/sdk/latest/modules/sdk/io/file.htm https://addons.mozilla.org/en-US/developers/docs/sdk/latest/modules/sdk/io/file.htm

The fileSDK的模块非常有限。当打开文件进行写入时，它总是会被截断（code https://github.com/mozilla/addon-sdk/blob/613de5ee8f5db7e81fd2d65416d8760c61a0bbd1/lib/sdk/io/file.js#L142-L144）。此外，它在主线程上使用完全同步的 I/O，这并不是一件好事，因为它会在 I/O 期间阻塞整个 UI。

您可能应该通过以下方式使用另一种机制chrome https://addons.mozilla.org/en-US/developers/docs/sdk/latest/dev-guide/tutorials/chrome.html模块。看OS.File https://developer.mozilla.org/en-US/docs/JavaScript_OS.File/OS.File_for_the_main_thread和/或MDN 文件 I/O 片段 https://developer.mozilla.org/en-US/docs/Code_snippets/File_I_O#Writing_to_a_file.