Error while executing python code
Question: 
    # -*- coding: utf-8 -*-
    # coding: utf-8
    import sys
    
    import os
    
    import time
    
    b = 'sudo tshark -i eth0 -R “tcp contains “attack”” -T fields -e ip.src -a duration:60>output.txt'
    
    a = os.popen(b)
    
    time.sleep(32)
    
    f = open('output.txt','r')
    
    text = 'IP address of attacker is'
    
    print (text), f.read()
    
    f.close
    

I am trying to execute this code to capture packets using tshark but i am
getting this error:

    
    
    tshark: "�" was unexpected in this context.
    

Please help me why that error is caused, thank you


Answer: The error message is because `tshark` tries to disable some dangerous
functions in Lua like `dofile`.

If you don't need Lua in tshark, you can disable Lua support: edit `init.lua`,
change `disable_lua = false` to `disable_lua = true`.

If you need Lua support, read [Platform-Specific information about capture
privileges](http://wiki.wireshark.org/CaptureSetup/CapturePrivileges), see how
to capture packets without root rivilege.

