奇怪的网络问题

今天测试网络的发送超时，写的简单程序，却出现异常行为，不解中

server.py

server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server_socket.setsockopt(socket.SOL_SOCKET,socket.SO_REUSEADDR,1)
server_socket.bind(("", 1234))
server_socket.listen(5)

print "begin accept"
client_socket,address = server_socket.accept()
client_socket.setsockopt(socket.SOL_SOCKET,socket.SO_RCVBUF,0)
print "accept finish"
ret = client_socket.recv(4096)
print ret
time.sleep(10000000)
print "ret",ret

client.py:

import socket
import time

client_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client_socket.connect(("localhost",1234))

print client_socket

print "send data"
client_socket.setsockopt(socket.SOL_SOCKET,socket.SO_SNDBUF,1)

total = 0
while 1:
    ret = client_socket.send("hello,world")
    total += ret
    print "send %d" % total

time.sleep(100)

我先启动server，然后启动client，一切正常。然后我关闭client(ctrl + c) , 在执行client，奇怪的是client还可以连上server，并且可以继续发送数据！！！但是server只做了一次accept，这后一次是怎样连上的啊？
通过netstat观察，确实是有个新的连接
tcp        0      0 localhost.localdomain:57341 localhost.localdomain:1234  FIN_WAIT2   
tcp        0     12 localhost.localdomain:57340 localhost.localdomain:1234  FIN_WAIT1  

这后一个连接是怎样连上的啊？

你加上server_socket.close()再试试