前面有了TCP server和TCP client。在这个文章中我们建立tcp连接并且进行数据的发送。

例子，经常用到的echo功能。TCP client连接到server， 向server发送message，server端收到消息打印，并将消息返回给client。

server端代码：

import socketimport sysdef start_tcp_server(ip, port):    #create socket    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)        server_address = (ip, port)    #bind port    print 'starting listen on ip %s, port %s'%server_address    sock.bind(server_address)        #starting listening, allow only one connection    try:        sock.listen(1)    except socket.error, e:        print "fail to listen on port %s"%e        sys.exit(1)            while True:        print "waiting for connection"        client,addr = sock.accept()        print 'having a connection'        data = client.recv(1024)        print 'recving data:'  +  data                print 'send data back'        client.sendall(data)        client.close()        if __name__ == '__main__':    start_tcp_server('172.125.0.1', 12346)

　　

client端代码：

import socketimport sysdef start_tcp_client(ip, port):        #server port and ip    server_ip = ip    servr_port = port        tcp_client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)        try:        tcp_client.connect((server_ip, servr_port))    except socket.error:        print 'fail to setup socket connection'    else:        print 'sending..........'        tcp_client.sendall("echo message")                print 'reading...........'        print tcp_client.recv(1024)    tcp_client.close()start_tcp_client('172.125.0.1', 12346)

　　

 

 

这里面用到了收发函数，其中缓存的大小已经指定或者采用默认值。

如何查看一个连接的缓存大小并且在必要的时候修改它。

socket.getsockopt(socket.SOL_SOCKET, socket.SO_SNDBUF)

socket.setsockopt(socket.SOL_SOCKET, socket.SO_SNDBUF, size)

如果是接受方的缓存，参数名称为SO_RCVBUF.

socket.getsockopt(socket.SOL_SOCKET, socket.SO_RCVBUF)

socket.setsockopt(socket.SOL_SOCKET, socket.SO_RCVBUF, size)

 

 

我们增加代码加入参数，使用argparser 模块

client:

import socketimport sysimport argparsedef start_tcp_client(ip, port):        #server port and ip    server_ip = ip    servr_port = port        tcp_client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)        try:        tcp_client.connect((server_ip, servr_port))    except socket.error:        print 'fail to setup socket connection'    else:        print 'sending..........'        tcp_client.sendall("echo message")                print 'reading...........'        print tcp_client.recv(1024)    tcp_client.close()if __name__ == '__main__':    arg = argparse.ArgumentParser(description='input port and ip')    arg.add_argument('-i', help='input the ip address')    arg.add_argument('-p', type=int, help='input the port')    args = arg.parse_args()    print 'ip : port ' + args.i +" " + str(args.p)    start_tcp_client(args.i, args.p)

　　

server:

import socketimport sysimport argparsedef start_tcp_server(ip, port):    #create socket    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)        server_address = (ip, port)    #bind port    print 'starting listen on ip %s, port %s'%server_address    sock.bind(server_address)        #starting listening, allow only one connection    try:        sock.listen(1)    except socket.error, e:        print "fail to listen on port %s"%e        sys.exit(1)            while True:        print "waiting for connection"        client,addr = sock.accept()        print 'having a connection'        data = client.recv(1024)        print 'recving data:'  +  data                print 'send data back'        client.sendall(data)        client.close()        if __name__ == '__main__':    arg = argparse.ArgumentParser(description='input port and ip')    arg.add_argument('-i', help='input the ip address')    arg.add_argument('-p', type=int, help='input the port')    args = arg.parse_args()    print 'ip : port ' + args.i +" " + str(args.p)    start_tcp_server(args.i, args.p)

　

 

调用：

启动server：

# python socket_1_server.py -i 10.135.13.171 -p 12345

ip : port 10.135.13.171 12345

starting listen on ip 10.135.13.171, port 12345

waiting for connection

启动client：

# python socket_2_client.py -i 10.135.13.171 -p 12345

ip : port 10.135.13.171 12345

sending..........

reading...........

echo message

server侧打印：

having a connection

recving data:echo message

send data back

waiting for connectio