最近计划重写downloadPlus_fx98.uc.js，原来的快速保存列表是写死的，准备改成从about:config读取，配置项不存在则列出所有盘符。
查了一下 win32 api，有个可以获取盘符的函数

https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-getlogicaldrivestringsw

之前就写过调用dll的代码，参数的类型都没试过，只能searchfox，搜一下，有参考，那就好办了。
https://searchfox.org/mozilla-central/source/toolkit/modules/subprocess/subprocess_shared_win.js

function getAllDrives() {
    let kernel32 = ctypes.open("kernel32.dll");
    let GetLogicalDriveStringsW = kernel32.declare('GetLogicalDriveStringsW', ctypes.winapi_abi, ctypes.unsigned_long, ctypes.uint32_t, ctypes.char16_t.ptr);
    let buffer = new (ctypes.ArrayType(ctypes.char16_t, 1024))();
    let rv = GetLogicalDriveStringsW(buffer.length, buffer);
    let resultLen = parseInt(rv.toString() || "0");
    let arr = [];
    if (!resultLen) {
        kernel32.close();
        return arr;
    }
    for (let i = 0; i < resultLen; i++) {
        arr[i] = buffer.addressOfElement(i).contents;
    }
    arr = arr.join('').split('\0').filter(el => el.length);
    kernel32.close();
    return arr;
}