python中socket使用，IO多路复用，socketserver

1、socket

2、IO多路复用

3、socketserver
Socket
socket起源于Unix，而Unix/Linux基本哲学之一就是“一切皆文件”，对于文件用【打开】【读写】【关闭】模式来操作。socket就是该模式的一个实现，socket即是一种特殊的文件，一些socket函数就是对其进行的操作（读/写IO、打开、关闭）

基本上，Socket 是任何一种计算机网络通讯中最基础的内容。例如当你在浏览器地址栏中输入 http://www.cnblogs.com/ 时，你会打开一个套接字，然后连接到 http://www.cnblogs.com/ 并读取响应的页面然后然后显示出来。而其他一些聊天客户端如 gtalk 和 skype 也是类似。任何网络通讯都是通过 Socket 来完成的。

Python 官方关于 Socket 的函数请看 http://docs.python.org/library/socket.html

socket和file的区别：

1、file模块是针对某个指定文件进行【打开】【读写】【关闭】

2、socket模块是针对 服务器端 和 客户端Socket 进行【打开】【读写】【关闭】
　　

import socket

sk = socket.socket()
sk.bind(("127.0.0.1",8080))
sk.listen(5)

conn,address = sk.accept()
sk.sendall(bytes("Hello world",encoding="utf-8"))

server

import socket

obj = socket.socket()
obj.connect(("127.0.0.1",8080))

ret = str(obj.recv(1024),encoding="utf-8")
print(ret)

socket更多功能

def bind(self, address): # real signature unknown; restored from __doc__
        """
        bind(address)
        
        Bind the socket to a local address.  For IP sockets, the address is a
        pair (host, port); the host must refer to the local host. For raw packet
        sockets the address is a tuple (ifname, proto [,pkttype [,hatype]])
        """
'''将套接字绑定到本地地址。是一个IP套接字的地址对(主机、端口),主机必须参考本地主机。'''
        pass

    def close(self): # real signature unknown; restored from __doc__
        """
        close()
        
        Close the socket.  It cannot be used after this call.
        """
        '''关闭socket'''
        pass

    def connect(self, address): # real signature unknown; restored from __doc__
        """
        connect(address)
        
        Connect the socket to a remote address.  For IP sockets, the address
        is a pair (host, port).
        """
        '''将套接字连接到远程地址。IP套接字的地址'''
        pass

    def connect_ex(self, address): # real signature unknown; restored from __doc__
        """
        connect_ex(address) -> errno
        
        This is like connect(address), but returns an error code (the errno value)
        instead of raising an exception when an error occurs.
        """
        pass

    def detach(self): # real signature unknown; restored from __doc__
        """
        detach()
        
        Close the socket object without closing the underlying file descriptor.
        The object cannot be used after this call, but the file descriptor
        can be reused for other purposes.  The file descriptor is returned.
        """
'''关闭套接字对象没有关闭底层的文件描述符。'''
        pass

    def fileno(self): # real signature unknown; restored from __doc__
        """
        fileno() -> integer
        
        Return the integer file descriptor of the socket.
        """
        '''返回整数的套接字的文件描述符。'''
        return 0

    def getpeername(self): # real signature unknown; restored from __doc__
        """
        getpeername() -> address info
        
        Return the address of the remote endpoint.  For IP sockets, the address
        info is a pair (hostaddr, port).
            """
        '''返回远程端点的地址。IP套接字的地址'''
        pass

    def getsockname(self): # real signature unknown; restored from __doc__
        """
        getsockname() -> address info
        
        Return the address of the local endpoint.  For IP sockets, the address
        info is a pair (hostaddr, port).
        """
        '''返回远程端点的地址。IP套接字的地址'''
        pass

    def getsockopt(self, level, option, buffersize=None): # real signature unknown; restored from __doc__
        """
        getsockopt(level, option[, buffersize]) -> value
        
        Get a socket option.  See the Unix manual for level and option.
        If a nonzero buffersize argument is given, the return value is a
        string of that length; otherwise it is an integer.
        """
        '''得到一个套接字选项'''
        pass

    def gettimeout(self): # real signature unknown; restored from __doc__
        """
        gettimeout() -> timeout
        
        Returns the timeout in seconds (float) associated with socket 
        operations. A timeout of None indicates that timeouts on socket 
        operations are disabled.
        """
        '''返回的超时秒数(浮动)与套接字相关联'''
        return timeout

    def ioctl(self, cmd, option): # real signature unknown; restored from __doc__
        """
        ioctl(cmd, option) -> long
        
        Control the socket with WSAIoctl syscall. Currently supported 'cmd' values are
        SIO_RCVALL:  'option' must be one of the socket.RCVALL_* constants.
        SIO_KEEPALIVE_VALS:  'option' is a tuple of (onoff, timeout, interval).
        """
        return 0

    def listen(self, backlog=None): # real signature unknown; restored from __doc__
        """
        listen([backlog])
        
        Enable a server to accept connections.  If backlog is specified, it must be
        at least 0 (if it is lower, it is set to 0); it specifies the number of
        unaccepted connections that the system will allow before refusing new
        connections. If not specified, a default reasonable value is chosen.
        """
        '''使服务器能够接受连接。'''
        pass

    def recv(self, buffersize, flags=None): # real signature unknown; restored from __doc__
        """
        recv(buffersize[, flags]) -> data
        
        Receive up to buffersize bytes from the socket.  For the optional flags
        argument, see the Unix manual.  When no data is available, block until
        at least one byte is available or until the remote end is closed.  When
        the remote end is closed and all data is read, return the empty string.
        """
'''当没有数据可用,阻塞,直到至少一个字节是可用的或远程结束之前关闭。'''
        pass

    def recvfrom(self, buffersize, flags=None): # real signature unknown; restored from __doc__
        """
        recvfrom(buffersize[, flags]) -> (data, address info)
        
        Like recv(buffersize, flags) but also return the sender's address info.
        """
        pass

    def recvfrom_into(self, buffer, nbytes=None, flags=None): # real signature unknown; restored from __doc__
        """
        recvfrom_into(buffer[, nbytes[, flags]]) -> (nbytes, address info)
        
        Like recv_into(buffer[, nbytes[, flags]]) but also return the sender's address info.
        """
        pass

    def recv_into(self,