通过 readdir(3) 异步地读取下一个目录条目作为 fs.Dirent

读取完成后,将使用 fs.Direntnull(如果读取不到更多的目录条目)调用 callback


Asynchronously read the next directory entry via readdir(3) as an fs.Dirent.

After the read is completed, the callback will be called with an fs.Dirent, or null if there are no more directory entries to read.

Directory entries returned by this function are in no particular order as provided by the operating system's underlying directory mechanisms. Entries added or removed while iterating over the directory may or may not be included in the iteration results.