fd_r_list, fd_w_list, fd_e_list = select.select(rlist, wlist, xlist, [timeout])

import socket
import select

s = socket.socket()
s.bind(('127.0.0.1',8888))
s.listen(5)
r_list = [s,]
num = 0
while True:
 rl, wl, error = select.select(r_list,[],[],10)
 num+=1
 print('counts is %s'%num)
 print("rl's length is %s"%len(rl))
 for fd in rl:
  if fd == s:
   conn, addr = fd.accept()
   r_list.append(conn)
   msg = conn.recv(200)
   conn.sendall(('first----%s'%conn.fileno()).encode())
  else:
   try:
    msg = fd.recv(200)
    fd.sendall('second'.encode())
   except ConnectionAbortedError:
    r_list.remove(fd)


s.close()

import socket

flag = 1
s = socket.socket()
s.connect(('127.0.0.1',8888))
while flag:
 input_msg = input('input>>>')
 if input_msg == '0':
  break
 s.sendall(input_msg.encode())
 msg = s.recv(1024)
 print(msg.decode())

s.close()

select.epoll(sizehint=-1, flags=0) 創(chuàng)建epoll對象


epoll.close()
Close the control file descriptor of the epoll object.關(guān)閉epoll對象的文件描述符

epoll.closed
True if the epoll object is closed.檢測epoll對象是否關(guān)閉

epoll.fileno()
Return the file descriptor number of the control fd.返回epoll對象的文件描述符

epoll.fromfd(fd)
Create an epoll object from a given file descriptor.根據(jù)指定的fd創(chuàng)建epoll對象

epoll.register(fd[, eventmask])
Register a fd descriptor with the epoll object.向epoll對象中注冊fd和對應(yīng)的事件

epoll.modify(fd, eventmask)
Modify a registered file descriptor.修改fd的事件

epoll.unregister(fd)
Remove a registered file descriptor from the epoll object.取消注冊

epoll.poll(timeout=-1, maxevents=-1)
Wait for events. timeout in seconds (float)阻塞，直到注冊的fd事件發(fā)生,會(huì)返回一個(gè)dict，格式為：{(fd1,event1),(fd2,event2),……(fdn,eventn)}

EPOLLIN Available for read 可讀 狀態(tài)符為1
EPOLLOUT Available for write 可寫 狀態(tài)符為4
EPOLLPRI Urgent data for read
EPOLLERR Error condition happened on the assoc. fd 發(fā)生錯(cuò)誤 狀態(tài)符為8
EPOLLHUP Hang up happened on the assoc. fd 掛起狀態(tài)
EPOLLET Set Edge Trigger behavior, the default is Level Trigger behavior 默認(rèn)為水平觸發(fā)，設(shè)置該事件后則邊緣觸發(fā)
EPOLLONESHOT Set one-shot behavior. After one event is pulled out, the fd is internally disabled
EPOLLRDNORM Equivalent to EPOLLIN
EPOLLRDBAND Priority data band can be read.
EPOLLWRNORM Equivalent to EPOLLOUT
EPOLLWRBAND Priority data may be written.
EPOLLMSG Ignored.

import socket
import select

s = socket.socket()
s.bind(('127.0.0.1',8888))
s.listen(5)
epoll_obj = select.epoll()
epoll_obj.register(s,select.EPOLLIN)
connections = {}
while True:
 events = epoll_obj.poll()
 for fd, event in events:
  print(fd,event)
  if fd == s.fileno():
   conn, addr = s.accept()
   connections[conn.fileno()] = conn
   epoll_obj.register(conn,select.EPOLLIN)
   msg = conn.recv(200)
   conn.sendall('ok'.encode())
  else:
   try:
    fd_obj = connections[fd]
    msg = fd_obj.recv(200)
    fd_obj.sendall('ok'.encode())
   except BrokenPipeError:
    epoll_obj.unregister(fd)
    connections[fd].close()
    del connections[fd]

s.close()
epoll_obj.close()

import socket

flag = 1
s = socket.socket()
s.connect(('127.0.0.1',8888))
while flag:
 input_msg = input('input>>>')
 if input_msg == '0':
  break
 s.sendall(input_msg.encode())
 msg = s.recv(1024)
 print(msg.decode())

s.close()