Python client / server question
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                AustinM
            
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        Published on 2011-01-09T22:44:05Z
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            2011/01/09
            22:53 UTC
        
        
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I'm working on a bit of a project in python. I have a client and a server. The server listens for connections and once a connection is received it waits for input from the client. The idea is that the client can connect to the server and execute system commands such as ls and cat. This is my server code:
import sys, os, socket
host = ''                
port = 50105
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((host, port))
print("Server started on port: ", port)
s.listen(5)
print("Server listening\n")
conn, addr = s.accept()
print 'New connection from ', addr
while (1):
    rc = conn.recv(5)
    pipe = os.popen(rc)
    rl = pipe.readlines()
    file = conn.makefile('w', 0)
    file.writelines(rl[:-1])
    file.close()
    conn.close()
And this is my client code:
import sys, socket
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
host = 'localhost'
port = input('Port: ')
s.connect((host, port))
cmd = raw_input('$ ')
s.send(cmd) 
file = s.makefile('r', 0)
sys.stdout.writelines(file.readlines())
When I start the server I get the right output, saying the server is listening. But when I connect with my client and type a command the server exits with this error:
Traceback (most recent call last):
File "server.py", line 21, in <module>
  rc = conn.recv(2)
File "/usr/lib/python2.6/socket.py", line 165, in _dummy
  raise error(EBADF, 'Bad file descriptor')
socket.error: [Errno 9] Bad file descriptor
On the client side, I get the output of ls but the server gets screwed up.
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