python 实现简单client与server
socket.getaddrinfo(host, port, family=0, socktype=0, proto=0, flags=0)#根据给定的参数host/port，相应的转换成一个包含用于创建socket对象的五元组，#参数host为域名，以字符串形式给出代表一个IPV4/IPV6地址或者None.#参数port如果字符串形式就代表一个服务名，比如“http”"ftp""email"等，或者为数字，或者为None#参数family为地主族，可以为AF_INET ，AF_INET6 ，AF_UNIX.#参数socketype可以为SOCK_STREAM(TCP)或者SOCK_DGRAM(UDP)#参数proto通常为0可以直接忽略#参数flags为AI_*的组合，比如AI_NUMERICHOST，它会影响函数的返回值#附注：给参数host,port传递None时建立在C基础，通过传递NULL。#该函数返回一个五元组(family, socktype, proto, canonname, sockaddr)，同时第五个参数sockaddr也是一个二元组(address, port)# Echo server programimport socketimport sysHOST = None # Symbolic name meaning all available interfacesPORT = 8888 # Arbitrary non-privileged ports = Nonefor res in socket.getaddrinfo(HOST, PORT, socket.AF_UNSPEC, socket.SOCK_STREAM, 0, socket.AI_PASSIVE): af, socktype, proto, canonname, sa = res try: #根据getaddrinfo()的返回信息初始化socket s = socket.socket(af, socktype, proto) except socket.error, err_msg: print err_msg #回显异常信息 s = None continue try: #sa是(host,port)的二元组 s.bind(sa) #监听客户端请求 s.listen(1) except socket.error, err_msg: print err_msg s.close() s = None continue breakif s is None: print 'could not open socket' sys.exit(1) conn, addr = s.accept()print 'Connected by', addrwhile 1: data = conn.recv(1024)# 2）接受数据 if not data: break conn.send(data)# 3）并返回2中接受到得数据conn.close()# Echo client programimport socketimport sysHOST = '127.0.0.1' # The remote hostPORT = 8888 # The same port as used by the servers = Nonefor res in socket.getaddrinfo(HOST, PORT, socket.AF_UNSPEC, socket.SOCK_STREAM): af, socktype, proto, canonname, sa = res try: s = socket.socket(af, socktype, proto) except socket.error, msg: s = None continue try: s.connect(sa) except socket.error, msg: s.close() s = None continue breakif s is None: print 'could not open socket' sys.exit(1) s.sendall('Hello, world')# 1）发送数据data = s.recv(1024)# 4）接受服务器回显的数据s.close()print 'Received', repr(data) #打印输出