The gnet v2.7.0 is officially released!
In this release, most of the core internal packages used by gnet are now available outside of gnet!
Take netpoll package as an example:
Package netpoll provides a portable event-driven interface for network I/O.
The underlying facility of event notification is OS-specific:
With the help of the netpoll package, you can easily build your own high-performance
event-driven network applications based on epoll/kqueue.
The Poller represents the event notification facility whose backend is epoll or kqueue.
The OpenPoller function creates a new Poller instance:
poller, err := netpoll.OpenPoller()if err != nil {// handle error}defer poller.Close()addr, err := net.ResolveTCPAddr("tcp", "127.0.0.1:9090")if err != nil {// handle error}c, err := net.DialTCP("tcp", nil, addr)if err != nil {// handle error}f, err := c.File()if err != nil {// handle error}closeClient := func() {c.Close()f.Close()}defer closeClient()
The PollAttachment consists of a file descriptor and its callback function.
PollAttachment is used to register a file descriptor to Poller.
The callback function is called when an event occurs on the file descriptor:
pa := netpoll.PollAttachment{FD: int(f.Fd()),Callback: func(fd int, event netpoll.IOEvent, flags netpoll.IOFlags) error {if netpoll.IsErrorEvent(event, flags) {closeClient()return errors.ErrEngineShutdown}if netpoll.IsReadEvent(event) {buf := make([]byte, 64)// Read data from the connection._, err := c.Read(buf)if err != nil {closeClient()return errors.ErrEngineShutdown}// Process the data...}if netpoll.IsWriteEvent(event) {// Write data to the connection._, err := c.Write([]byte("hello"))if err != nil {closeClient()return errors.ErrEngineShutdown}}return nil}}if err := poller.AddReadWrite(&pa, false); err != nil {// handle error}
The Poller.Polling function starts the event loop monitoring file descriptors and
waiting for I/O events to occur:
poller.Polling(func(fd int, event netpoll.IOEvent, flags netpoll.IOFlags) error {return pa.Callback(fd, event, flags)})
Or
poller.Polling()
if you've enabled the build tag poll_opt.
Check out gnet/pkg for more details.
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