python使用epoll实现服务端的方法

如下所示：

#!/usr/bin/python
# -*- coding: UTF-8 -*-
import socket
import select

send_data = "hello world!"
send_len = len(send_data)
recv_len = 1024
tcp_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
tcp_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
addr = ("0.0.0.0", 8765)
tcp_socket.bind(addr)
tcp_socket.listen(5)
tcp_socket.setblocking(False)
epoll = select.epoll()
'''(边缘触发)select.EPOLLIN | select.EPOLLET'''
epoll.register(tcp_socket.fileno(), select.EPOLLIN)
'''因为epoll返回的触发事件对应的是套接字文件描述符，所以需要在字典中加入对应关系'''
fd_to_socket = {tcp_socket.fileno():tcp_socket}

while True :
events = epoll.poll(-1)
for fd, event in events:
 fd_socket = fd_to_socket[fd]
 if fd == tcp_socket.fileno():
  while True:
   try:
    new_socket, new_addr = fd_socket.accept()
   except socket.error as e:
    (errno, err_msg) = e
    print errno
    print err_msg
    if errno == 11:
     break
   print "new accpet:", new_addr
   new_socket.setblocking(False)
   new_socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
   epoll.register(new_socket.fileno(), select.EPOLLIN)
   fd_to_socket[new_socket.fileno()] = new_socket
 elif event&select.EPOLLIN:
  recv_datas = []
  recd = 0
  while (recd < recv_len):
   try:
    recv_data = fd_socket.recv(recv_len - recd)
    '''处理读的正常关闭'''
    if recv_data == "":
     print "close socket"
     epoll.unregister(fd)
     fd_to_socket[fd].close()
     del fd_to_socket[fd]
     break
    else:
     recv_datas.append(recv_data)
     recd = recd + len(recv_data)
   '''处理异常关闭(EAGAIN,EINTR)'''
   except socket.error as e:
    (errno, err_msg) = e
    print errno
    print err_msg
    '''因为用的水平触发，EAGAIN我们跳出循环，等待下次触发再读就好了'''
    if errno == 11:
     break
    '''软中断打断了还要继续读'''
    elif errno == 4:
     continue
    '''其它错误我们直接关闭套接字'''
    else:
     print "close socket"
     epoll.unregister(fd)
     fd_to_socket[fd].close()
     del fd_to_socket[fd]
     break
   print repr(recv_datas)
   total_send = 0
   while total_send < send_len:
    sent = fd_socket.send(send_data[total_send:])
    if sent == 0:
     print "close socket"
     epoll.unregister(fd)
     fd_to_socket[fd].close()
     del fd_to_socket[fd]
     break
    else:
     print repr(send_data[total_send:])
     total_send = total_send + sent

其实这里的异常处理我们也可以用

except IOError as e:
 print e.errno
 print e.strerror

来源：https://blog.csdn.net/peng314899581/article/details/78066087