def METHOD_NAME():
    """Returns a list containing all network interfaces."""
    # Get ifconfig output
    subproc = subprocess.Popen(
        [conf.prog.ifconfig],
        close_fds=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE
    )
    stdout, stderr = subproc.communicate()
    if subproc.returncode:
        raise Scapy_Exception("Failed to execute ifconfig: (%s)" %
                              (plain_str(stderr)))
    interfaces = [
        line[:line.find(':')] for line in plain_str(stdout).splitlines()
        if ": flags" in line.lower()
    ]
    return interfaces