jq tounch id attar发生两次(jq tounch id attar occuring twice)

 绑定文件句柄仅部分在perl中实现，不适用于EV。 一般情况下，绑定句柄不能与事件库一起使用：虽然某些特定情况可能有效，但在大多数使用绑定句柄的情况下，它们无法工作，因为基础文件描述符的准备就绪通知与准备就绪无关绑定句柄的通知。 
 
 如果你的目标只是在一个真实的文件描述符周围有一个东西包装器，那么一种方法就是复制IO :: Handle和/或FileHandle做的事情（非常难看，但是在perl中工作的唯一方法），或者将它们用作基类。 这不允许你做一些有趣的事情，比如挂钩读写，但是有可能挂钩它们会使它们与事件库不兼容。 
 
 另一种方法是实现perlio层（PerlIO :: via）。 根据我的经验，这个模块有点脆弱，但为您提供了所有选项。 同样，如果你引入缓冲或更有趣的东西，将文件描述符与实际的I / O分离，那么它就无法工作。 
 
 最后，如果要添加新类型的句柄，则可以创建新的观察者类型。 这可以像拥有一个函数my_handle_io_watcher一样简单，它可以处理你的句柄，检查准备情况并创建所需的低级观察者。 

tied file handles are only partially implemented in perl, and don't work with EV. Tied handles cannot be made to work with an event library in general: While some specific cases might work, in most cases where tied handles are used, they can't work because the readiness notification of an underlying file descriptor doesn't relate to readiness notifications of the tied handle.
 
If your goal is to merely have a thing wrapper around a real file descriptor, then one way to do it is to copy what IO::Handle and/or FileHandle do (very ugly, but the only way that works in perl), or use them as base classes. This doesn't allow you to do interesting things such as hooking reads and writes, but chances are hooking them makes them incompatible with event libraries.
 
Another way is to implement a perlio layer (PerlIO::via). In my experience, this module is a bit fragile, but gives you all the options. Again, if you introduce buffering or more interesting things that decouple the file descriptor from the actual I/O, then it can't be made to work.
 
Lastly, if you want to add a new type of handle, then you can create a new watcher type. This can be as simple as having a function my_handle_io_watcher that takes your handle, checks for readiness and creates the kind of low-level watcher that is required.