FM / python3.9

/usr/lib64/python3.9

Name	Size	Mode	Actions
asyncio/	-	0755	rm
collections/	-	0755	rm
concurrent/	-	0755	rm
config-3.9-x86_64-linux-gnu/	-	0755	rm
ctypes/	-	0755	rm
curses/	-	0755	rm
dbm/	-	0755	rm
distutils/	-	0755	rm
email/	-	0755	rm
encodings/	-	0755	rm
ensurepip/	-	0755	rm
html/	-	0755	rm
http/	-	0755	rm
importlib/	-	0755	rm
json/	-	0755	rm
lib-dynload/	-	0755	rm
lib2to3/	-	0755	rm
logging/	-	0755	rm
multiprocessing/	-	0755	rm
pydoc_data/	-	0755	rm
site-packages/	-	0755	rm
sqlite3/	-	0755	rm
unittest/	-	0755	rm
urllib/	-	0755	rm
venv/	-	0755	rm
wsgiref/	-	0755	rm
xml/	-	0755	rm
xmlrpc/	-	0755	rm
zoneinfo/	-	0755	rm
__pycache__/	-	0755	rm
abc.py	4920	0644	edit dl rm
aifc.py	32605	0644	edit dl rm
antigravity.py	500	0644	edit dl rm
argparse.py	98119	0644	edit dl rm
ast.py	56256	0644	edit dl rm
asynchat.py	11321	0644	edit dl rm
asyncore.py	20102	0644	edit dl rm
base64.py	19859	0755	edit dl rm
bdb.py	31389	0644	edit dl rm
binhex.py	14784	0644	edit dl rm
bisect.py	2350	0644	edit dl rm
bz2.py	12447	0644	edit dl rm
calendar.py	24832	0644	edit dl rm
cgi.py	33932	0755	edit dl rm
cgitb.py	12096	0644	edit dl rm
chunk.py	5435	0644	edit dl rm
cmd.py	14860	0644	edit dl rm
code.py	10622	0644	edit dl rm
codecs.py	36673	0644	edit dl rm
codeop.py	6326	0644	edit dl rm
colorsys.py	4064	0644	edit dl rm
compileall.py	20105	0644	edit dl rm
configparser.py	54584	0644	edit dl rm
contextlib.py	24624	0644	edit dl rm
contextvars.py	129	0644	edit dl rm
copy.py	8650	0644	edit dl rm
copyreg.py	7274	0644	edit dl rm
cProfile.py	6345	0755	edit dl rm
crypt.py	3819	0644	edit dl rm
csv.py	16144	0644	edit dl rm
dataclasses.py	49586	0644	edit dl rm
datetime.py	89177	0644	edit dl rm
decimal.py	320	0644	edit dl rm
difflib.py	83307	0644	edit dl rm
dis.py	20570	0644	edit dl rm
doctest.py	104568	0644	edit dl rm
enum.py	39440	0644	edit dl rm
filecmp.py	10024	0644	edit dl rm
fileinput.py	14791	0644	edit dl rm
fnmatch.py	6004	0644	edit dl rm
formatter.py	15143	0644	edit dl rm
fractions.py	24323	0644	edit dl rm
ftplib.py	35496	0644	edit dl rm
functools.py	38881	0644	edit dl rm
genericpath.py	5246	0644	edit dl rm
getopt.py	7489	0644	edit dl rm
getpass.py	5990	0644	edit dl rm
gettext.py	27266	0644	edit dl rm
glob.py	5823	0644	edit dl rm
graphlib.py	9573	0644	edit dl rm
gzip.py	21772	0644	edit dl rm
hashlib.py	8069	0644	edit dl rm
heapq.py	22877	0644	edit dl rm
hmac.py	8043	0644	edit dl rm
imaplib.py	55256	0644	edit dl rm
imghdr.py	3808	0644	edit dl rm
imp.py	10536	0644	edit dl rm
inspect.py	118235	0644	edit dl rm
io.py	3541	0644	edit dl rm
ipaddress.py	80924	0644	edit dl rm
keyword.py	1047	0644	edit dl rm
LICENSE.txt	13937	0644	edit dl rm
linecache.py	5461	0644	edit dl rm
locale.py	78271	0644	edit dl rm
lzma.py	13231	0644	edit dl rm
mailbox.py	78794	0644	edit dl rm
mailcap.py	9116	0644	edit dl rm
mimetypes.py	21564	0644	edit dl rm
modulefinder.py	24401	0644	edit dl rm
netrc.py	5566	0644	edit dl rm
nntplib.py	41023	0644	edit dl rm
ntpath.py	26460	0644	edit dl rm
nturl2path.py	2887	0644	edit dl rm
numbers.py	10338	0644	edit dl rm
opcode.py	5660	0644	edit dl rm
operator.py	10751	0644	edit dl rm
optparse.py	60369	0644	edit dl rm
os.py	39065	0644	edit dl rm
pathlib.py	51134	0644	edit dl rm
pdb.py	63237	0755	edit dl rm
pickle.py	64920	0644	edit dl rm
pickletools.py	93486	0644	edit dl rm
pipes.py	8916	0644	edit dl rm
pkgutil.py	24276	0644	edit dl rm
platform.py	40601	0755	edit dl rm
plistlib.py	28248	0644	edit dl rm
poplib.py	15198	0644	edit dl rm
posixpath.py	16146	0644	edit dl rm
pprint.py	22527	0644	edit dl rm
profile.py	22881	0755	edit dl rm
pstats.py	29326	0644	edit dl rm
pty.py	4807	0644	edit dl rm
pyclbr.py	15255	0644	edit dl rm
pydoc.py	109599	0755	edit dl rm
py_compile.py	8203	0644	edit dl rm
queue.py	11496	0644	edit dl rm
quopri.py	7266	0755	edit dl rm
random.py	31484	0644	edit dl rm
re.py	15861	0644	edit dl rm
reprlib.py	5267	0644	edit dl rm
rlcompleter.py	7648	0644	edit dl rm
runpy.py	13084	0644	edit dl rm
sched.py	6442	0644	edit dl rm
secrets.py	2036	0644	edit dl rm
selectors.py	19536	0644	edit dl rm
shelve.py	8527	0644	edit dl rm
shlex.py	13501	0644	edit dl rm
shutil.py	53030	0644	edit dl rm
signal.py	2438	0644	edit dl rm
site.py	22085	0644	edit dl rm
smtpd.py	34821	0755	edit dl rm
smtplib.py	45405	0755	edit dl rm
sndhdr.py	7099	0644	edit dl rm
socket.py	36915	0644	edit dl rm
socketserver.py	27296	0644	edit dl rm
sre_compile.py	27973	0644	edit dl rm
sre_constants.py	7177	0644	edit dl rm
sre_parse.py	40779	0644	edit dl rm
ssl.py	52622	0644	edit dl rm
stat.py	5485	0644	edit dl rm
statistics.py	38067	0644	edit dl rm
string.py	10566	0644	edit dl rm
stringprep.py	12917	0644	edit dl rm
struct.py	257	0644	edit dl rm
subprocess.py	83564	0644	edit dl rm
sunau.py	18158	0644	edit dl rm
symbol.py	2281	0644	edit dl rm
symtable.py	7905	0644	edit dl rm
sysconfig.py	25557	0644	edit dl rm
tabnanny.py	11406	0755	edit dl rm
tarfile.py	112939	0755	edit dl rm
telnetlib.py	23254	0644	edit dl rm
tempfile.py	27963	0644	edit dl rm
textwrap.py	19407	0644	edit dl rm
this.py	1003	0644	edit dl rm
threading.py	54176	0644	edit dl rm
timeit.py	13480	0755	edit dl rm
token.py	2368	0644	edit dl rm
tokenize.py	25883	0644	edit dl rm
trace.py	29207	0755	edit dl rm
traceback.py	24660	0644	edit dl rm
tracemalloc.py	18047	0644	edit dl rm
tty.py	879	0644	edit dl rm
types.py	9785	0644	edit dl rm
typing.py	77044	0644	edit dl rm
uu.py	7277	0644	edit dl rm
uuid.py	27324	0644	edit dl rm
warnings.py	19688	0644	edit dl rm
wave.py	18004	0644	edit dl rm
weakref.py	21560	0644	edit dl rm
webbrowser.py	24083	0755	edit dl rm
xdrlib.py	5913	0644	edit dl rm
zipapp.py	7535	0644	edit dl rm
zipfile.py	88899	0644	edit dl rm
zipimport.py	30765	0644	edit dl rm
_aix_support.py	3389	0644	edit dl rm
_bootlocale.py	1801	0644	edit dl rm
_bootsubprocess.py	2675	0644	edit dl rm
_collections_abc.py	29374	0644	edit dl rm
_compat_pickle.py	8749	0644	edit dl rm
_compression.py	5340	0644	edit dl rm
_markupbase.py	14623	0644	edit dl rm
_osx_support.py	21773	0644	edit dl rm
_pydecimal.py	228666	0644	edit dl rm
_pyio.py	93316	0644	edit dl rm
_py_abc.py	6189	0644	edit dl rm
_sitebuiltins.py	3115	0644	edit dl rm
_strptime.py	25277	0644	edit dl rm
_sysconfigdata__linux_x86_64-linux-gnu.py	41236	0644	edit dl rm
_threading_local.py	7220	0644	edit dl rm
_weakrefset.py	5923	0644	edit dl rm
__future__.py	5147	0644	edit dl rm
__phello__.foo.py	64	0644	edit dl rm

Edit: /usr/lib64/python3.9/telnetlib.py (23254B)

r"""TELNET client class.

Based on RFC 854: TELNET Protocol Specification, by J. Postel and
J. Reynolds

Example:

>>> from telnetlib import Telnet
>>> tn = Telnet('www.python.org', 79)   # connect to finger port
>>> tn.write(b'guido\r\n')
>>> print(tn.read_all())
Login       Name               TTY         Idle    When    Where
guido    Guido van Rossum      pts/2        <Dec  2 11:10> snag.cnri.reston..

>>>

Note that read_all() won't read until eof -- it just reads some data
-- but it guarantees to read at least one byte unless EOF is hit.

It is possible to pass a Telnet object to a selector in order to wait until
more data is available.  Note that in this case, read_eager() may return b''
even if there was data on the socket, because the protocol negotiation may have
eaten the data.  This is why EOFError is needed in some cases to distinguish
between "no data" and "connection closed" (since the socket also appears ready
for reading when it is closed).

To do:
- option negotiation
- timeout should be intrinsic to the connection object instead of an
  option on one of the read calls only

"""

# Imported modules
import sys
import socket
import selectors
from time import monotonic as _time

__all__ = ["Telnet"]

# Tunable parameters
DEBUGLEVEL = 0

# Telnet protocol defaults
TELNET_PORT = 23

# Telnet protocol characters (don't change)
IAC  = bytes([255]) # "Interpret As Command"
DONT = bytes([254])
DO   = bytes([253])
WONT = bytes([252])
WILL = bytes([251])
theNULL = bytes([0])

SE  = bytes([240])  # Subnegotiation End
NOP = bytes([241])  # No Operation
DM  = bytes([242])  # Data Mark
BRK = bytes([243])  # Break
IP  = bytes([244])  # Interrupt process
AO  = bytes([245])  # Abort output
AYT = bytes([246])  # Are You There
EC  = bytes([247])  # Erase Character
EL  = bytes([248])  # Erase Line
GA  = bytes([249])  # Go Ahead
SB =  bytes([250])  # Subnegotiation Begin

# Telnet protocol options code (don't change)
# These ones all come from arpa/telnet.h
BINARY = bytes([0]) # 8-bit data path
ECHO = bytes([1]) # echo
RCP = bytes([2]) # prepare to reconnect
SGA = bytes([3]) # suppress go ahead
NAMS = bytes([4]) # approximate message size
STATUS = bytes([5]) # give status
TM = bytes([6]) # timing mark
RCTE = bytes([7]) # remote controlled transmission and echo
NAOL = bytes([8]) # negotiate about output line width
NAOP = bytes([9]) # negotiate about output page size
NAOCRD = bytes([10]) # negotiate about CR disposition
NAOHTS = bytes([11]) # negotiate about horizontal tabstops
NAOHTD = bytes([12]) # negotiate about horizontal tab disposition
NAOFFD = bytes([13]) # negotiate about formfeed disposition
NAOVTS = bytes([14]) # negotiate about vertical tab stops
NAOVTD = bytes([15]) # negotiate about vertical tab disposition
NAOLFD = bytes([16]) # negotiate about output LF disposition
XASCII = bytes([17]) # extended ascii character set
LOGOUT = bytes([18]) # force logout
BM = bytes([19]) # byte macro
DET = bytes([20]) # data entry terminal
SUPDUP = bytes([21]) # supdup protocol
SUPDUPOUTPUT = bytes([22]) # supdup output
SNDLOC = bytes([23]) # send location
TTYPE = bytes([24]) # terminal type
EOR = bytes([25]) # end or record
TUID = bytes([26]) # TACACS user identification
OUTMRK = bytes([27]) # output marking
TTYLOC = bytes([28]) # terminal location number
VT3270REGIME = bytes([29]) # 3270 regime
X3PAD = bytes([30]) # X.3 PAD
NAWS = bytes([31]) # window size
TSPEED = bytes([32]) # terminal speed
LFLOW = bytes([33]) # remote flow control
LINEMODE = bytes([34]) # Linemode option
XDISPLOC = bytes([35]) # X Display Location
OLD_ENVIRON = bytes([36]) # Old - Environment variables
AUTHENTICATION = bytes([37]) # Authenticate
ENCRYPT = bytes([38]) # Encryption option
NEW_ENVIRON = bytes([39]) # New - Environment variables
# the following ones come from
# http://www.iana.org/assignments/telnet-options
# Unfortunately, that document does not assign identifiers
# to all of them, so we are making them up
TN3270E = bytes([40]) # TN3270E
XAUTH = bytes([41]) # XAUTH
CHARSET = bytes([42]) # CHARSET
RSP = bytes([43]) # Telnet Remote Serial Port
COM_PORT_OPTION = bytes([44]) # Com Port Control Option
SUPPRESS_LOCAL_ECHO = bytes([45]) # Telnet Suppress Local Echo
TLS = bytes([46]) # Telnet Start TLS
KERMIT = bytes([47]) # KERMIT
SEND_URL = bytes([48]) # SEND-URL
FORWARD_X = bytes([49]) # FORWARD_X
PRAGMA_LOGON = bytes([138]) # TELOPT PRAGMA LOGON
SSPI_LOGON = bytes([139]) # TELOPT SSPI LOGON
PRAGMA_HEARTBEAT = bytes([140]) # TELOPT PRAGMA HEARTBEAT
EXOPL = bytes([255]) # Extended-Options-List
NOOPT = bytes([0])

# poll/select have the advantage of not requiring any extra file descriptor,
# contrarily to epoll/kqueue (also, they require a single syscall).
if hasattr(selectors, 'PollSelector'):
    _TelnetSelector = selectors.PollSelector
else:
    _TelnetSelector = selectors.SelectSelector

class Telnet:

"""Telnet interface class.

An instance of this class represents a connection to a telnet
    server.  The instance is initially not connected; the open()
    method must be used to establish a connection.  Alternatively, the
    host name and optional port number can be passed to the
    constructor, too.

Don't try to reopen an already connected instance.

This class has many read_*() methods.  Note that some of them
    raise EOFError when the end of the connection is read, because
    they can return an empty string for other reasons.  See the
    individual doc strings.

read_until(expected, [timeout])
        Read until the expected string has been seen, or a timeout is
        hit (default is no timeout); may block.

read_all()
        Read all data until EOF; may block.

read_some()
        Read at least one byte or EOF; may block.

read_very_eager()
        Read all data available already queued or on the socket,
        without blocking.

read_eager()
        Read either data already queued or some data available on the
        socket, without blocking.

read_lazy()
        Read all data in the raw queue (processing it first), without
        doing any socket I/O.

read_very_lazy()
        Reads all data in the cooked queue, without doing any socket
        I/O.

read_sb_data()
        Reads available data between SB ... SE sequence. Don't block.

set_option_negotiation_callback(callback)
        Each time a telnet option is read on the input flow, this callback
        (if set) is called with the following parameters :
        callback(telnet socket, command, option)
            option will be chr(0) when there is no option.
        No other action is done afterwards by telnetlib.

"""

def __init__(self, host=None, port=0,
                 timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
        """Constructor.

When called without arguments, create an unconnected instance.
        With a hostname argument, it connects the instance; port number
        and timeout are optional.
        """
        self.debuglevel = DEBUGLEVEL
        self.host = host
        self.port = port
        self.timeout = timeout
        self.sock = None
        self.rawq = b''
        self.irawq = 0
        self.cookedq = b''
        self.eof = 0
        self.iacseq = b'' # Buffer for IAC sequence.
        self.sb = 0 # flag for SB and SE sequence.
        self.sbdataq = b''
        self.option_callback = None
        if host is not None:
            self.open(host, port, timeout)

def open(self, host, port=0, timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
        """Connect to a host.

The optional second argument is the port number, which
        defaults to the standard telnet port (23).

Don't try to reopen an already connected instance.
        """
        self.eof = 0
        if not port:
            port = TELNET_PORT
        self.host = host
        self.port = port
        self.timeout = timeout
        sys.audit("telnetlib.Telnet.open", self, host, port)
        self.sock = socket.create_connection((host, port), timeout)

def __del__(self):
        """Destructor -- close the connection."""
        self.close()

def msg(self, msg, *args):
        """Print a debug message, when the debug level is > 0.

If extra arguments are present, they are substituted in the
        message using the standard string formatting operator.

"""
        if self.debuglevel > 0:
            print('Telnet(%s,%s):' % (self.host, self.port), end=' ')
            if args:
                print(msg % args)
            else:
                print(msg)

def set_debuglevel(self, debuglevel):
        """Set the debug level.

The higher it is, the more debug output you get (on sys.stdout).

"""
        self.debuglevel = debuglevel

def close(self):
        """Close the connection."""
        sock = self.sock
        self.sock = None
        self.eof = True
        self.iacseq = b''
        self.sb = 0
        if sock:
            sock.close()

def get_socket(self):
        """Return the socket object used internally."""
        return self.sock

def fileno(self):
        """Return the fileno() of the socket object used internally."""
        return self.sock.fileno()

def write(self, buffer):
        """Write a string to the socket, doubling any IAC characters.

Can block if the connection is blocked.  May raise
        OSError if the connection is closed.

"""
        if IAC in buffer:
            buffer = buffer.replace(IAC, IAC+IAC)
        sys.audit("telnetlib.Telnet.write", self, buffer)
        self.msg("send %r", buffer)
        self.sock.sendall(buffer)

def read_until(self, match, timeout=None):
        """Read until a given string is encountered or until timeout.

When no match is found, return whatever is available instead,
        possibly the empty string.  Raise EOFError if the connection
        is closed and no cooked data is available.

"""
        n = len(match)
        self.process_rawq()
        i = self.cookedq.find(match)
        if i >= 0:
            i = i+n
            buf = self.cookedq[:i]
            self.cookedq = self.cookedq[i:]
            return buf
        if timeout is not None:
            deadline = _time() + timeout
        with _TelnetSelector() as selector:
            selector.register(self, selectors.EVENT_READ)
            while not self.eof:
                if selector.select(timeout):
                    i = max(0, len(self.cookedq)-n)
                    self.fill_rawq()
                    self.process_rawq()
                    i = self.cookedq.find(match, i)
                    if i >= 0:
                        i = i+n
                        buf = self.cookedq[:i]
                        self.cookedq = self.cookedq[i:]
                        return buf
                if timeout is not None:
                    timeout = deadline - _time()
                    if timeout < 0:
                        break
        return self.read_very_lazy()

def read_all(self):
        """Read all data until EOF; block until connection closed."""
        self.process_rawq()
        while not self.eof:
            self.fill_rawq()
            self.process_rawq()
        buf = self.cookedq
        self.cookedq = b''
        return buf

def read_some(self):
        """Read at least one byte of cooked data unless EOF is hit.

Return b'' if EOF is hit.  Block if no data is immediately
        available.

"""
        self.process_rawq()
        while not self.cookedq and not self.eof:
            self.fill_rawq()
            self.process_rawq()
        buf = self.cookedq
        self.cookedq = b''
        return buf

def read_very_eager(self):
        """Read everything that's possible without blocking in I/O (eager).

Raise EOFError if connection closed and no cooked data
        available.  Return b'' if no cooked data available otherwise.
        Don't block unless in the midst of an IAC sequence.

"""
        self.process_rawq()
        while not self.eof and self.sock_avail():
            self.fill_rawq()
            self.process_rawq()
        return self.read_very_lazy()

def read_eager(self):
        """Read readily available data.

Raise EOFError if connection closed and no cooked data
        available.  Return b'' if no cooked data available otherwise.
        Don't block unless in the midst of an IAC sequence.

"""
        self.process_rawq()
        while not self.cookedq and not self.eof and self.sock_avail():
            self.fill_rawq()
            self.process_rawq()
        return self.read_very_lazy()

def read_lazy(self):
        """Process and return data that's already in the queues (lazy).

Raise EOFError if connection closed and no data available.
        Return b'' if no cooked data available otherwise.  Don't block
        unless in the midst of an IAC sequence.

"""
        self.process_rawq()
        return self.read_very_lazy()

def read_very_lazy(self):
        """Return any data available in the cooked queue (very lazy).

Raise EOFError if connection closed and no data available.
        Return b'' if no cooked data available otherwise.  Don't block.

"""
        buf = self.cookedq
        self.cookedq = b''
        if not buf and self.eof and not self.rawq:
            raise EOFError('telnet connection closed')
        return buf

def read_sb_data(self):
        """Return any data available in the SB ... SE queue.

Return b'' if no SB ... SE available. Should only be called
        after seeing a SB or SE command. When a new SB command is
        found, old unread SB data will be discarded. Don't block.

"""
        buf = self.sbdataq
        self.sbdataq = b''
        return buf

def set_option_negotiation_callback(self, callback):
        """Provide a callback function called after each receipt of a telnet option."""
        self.option_callback = callback

def process_rawq(self):
        """Transfer from raw queue to cooked queue.

Set self.eof when connection is closed.  Don't block unless in
        the midst of an IAC sequence.

"""
        buf = [b'', b'']
        try:
            while self.rawq:
                c = self.rawq_getchar()
                if not self.iacseq:
                    if c == theNULL:
                        continue
                    if c == b"\021":
                        continue
                    if c != IAC:
                        buf[self.sb] = buf[self.sb] + c
                        continue
                    else:
                        self.iacseq += c
                elif len(self.iacseq) == 1:
                    # 'IAC: IAC CMD [OPTION only for WILL/WONT/DO/DONT]'
                    if c in (DO, DONT, WILL, WONT):
                        self.iacseq += c
                        continue

self.iacseq = b''
                    if c == IAC:
                        buf[self.sb] = buf[self.sb] + c
                    else:
                        if c == SB: # SB ... SE start.
                            self.sb = 1
                            self.sbdataq = b''
                        elif c == SE:
                            self.sb = 0
                            self.sbdataq = self.sbdataq + buf[1]
                            buf[1] = b''
                        if self.option_callback:
                            # Callback is supposed to look into
                            # the sbdataq
                            self.option_callback(self.sock, c, NOOPT)
                        else:
                            # We can't offer automatic processing of
                            # suboptions. Alas, we should not get any
                            # unless we did a WILL/DO before.
                            self.msg('IAC %d not recognized' % ord(c))
                elif len(self.iacseq) == 2:
                    cmd = self.iacseq[1:2]
                    self.iacseq = b''
                    opt = c
                    if cmd in (DO, DONT):
                        self.msg('IAC %s %d',
                            cmd == DO and 'DO' or 'DONT', ord(opt))
                        if self.option_callback:
                            self.option_callback(self.sock, cmd, opt)
                        else:
                            self.sock.sendall(IAC + WONT + opt)
                    elif cmd in (WILL, WONT):
                        self.msg('IAC %s %d',
                            cmd == WILL and 'WILL' or 'WONT', ord(opt))
                        if self.option_callback:
                            self.option_callback(self.sock, cmd, opt)
                        else:
                            self.sock.sendall(IAC + DONT + opt)
        except EOFError: # raised by self.rawq_getchar()
            self.iacseq = b'' # Reset on EOF
            self.sb = 0
            pass
        self.cookedq = self.cookedq + buf[0]
        self.sbdataq = self.sbdataq + buf[1]

def rawq_getchar(self):
        """Get next char from raw queue.

Block if no data is immediately available.  Raise EOFError
        when connection is closed.

"""
        if not self.rawq:
            self.fill_rawq()
            if self.eof:
                raise EOFError
        c = self.rawq[self.irawq:self.irawq+1]
        self.irawq = self.irawq + 1
        if self.irawq >= len(self.rawq):
            self.rawq = b''
            self.irawq = 0
        return c

def fill_rawq(self):
        """Fill raw queue from exactly one recv() system call.

Block if no data is immediately available.  Set self.eof when
        connection is closed.

"""
        if self.irawq >= len(self.rawq):
            self.rawq = b''
            self.irawq = 0
        # The buffer size should be fairly small so as to avoid quadratic
        # behavior in process_rawq() above
        buf = self.sock.recv(50)
        self.msg("recv %r", buf)
        self.eof = (not buf)
        self.rawq = self.rawq + buf

def sock_avail(self):
        """Test whether data is available on the socket."""
        with _TelnetSelector() as selector:
            selector.register(self, selectors.EVENT_READ)
            return bool(selector.select(0))

def interact(self):
        """Interaction function, emulates a very dumb telnet client."""
        if sys.platform == "win32":
            self.mt_interact()
            return
        with _TelnetSelector() as selector:
            selector.register(self, selectors.EVENT_READ)
            selector.register(sys.stdin, selectors.EVENT_READ)

while True:
                for key, events in selector.select():
                    if key.fileobj is self:
                        try:
                            text = self.read_eager()
                        except EOFError:
                            print('*** Connection closed by remote host ***')
                            return
                        if text:
                            sys.stdout.write(text.decode('ascii'))
                            sys.stdout.flush()
                    elif key.fileobj is sys.stdin:
                        line = sys.stdin.readline().encode('ascii')
                        if not line:
                            return
                        self.write(line)

def mt_interact(self):
        """Multithreaded version of interact()."""
        import _thread
        _thread.start_new_thread(self.listener, ())
        while 1:
            line = sys.stdin.readline()
            if not line:
                break
            self.write(line.encode('ascii'))

def listener(self):
        """Helper for mt_interact() -- this executes in the other thread."""
        while 1:
            try:
                data = self.read_eager()
            except EOFError:
                print('*** Connection closed by remote host ***')
                return
            if data:
                sys.stdout.write(data.decode('ascii'))
            else:
                sys.stdout.flush()

def expect(self, list, timeout=None):
        """Read until one from a list of a regular expressions matches.

The first argument is a list of regular expressions, either
        compiled (re.Pattern instances) or uncompiled (strings).
        The optional second argument is a timeout, in seconds; default
        is no timeout.

Return a tuple of three items: the index in the list of the
        first regular expression that matches; the re.Match object
        returned; and the text read up till and including the match.

If EOF is read and no text was read, raise EOFError.
        Otherwise, when nothing matches, return (-1, None, text) where
        text is the text received so far (may be the empty string if a
        timeout happened).

If a regular expression ends with a greedy match (e.g. '.*')
        or if more than one expression can match the same input, the
        results are undeterministic, and may depend on the I/O timing.

"""
        re = None
        list = list[:]
        indices = range(len(list))
        for i in indices:
            if not hasattr(list[i], "search"):
                if not re: import re
                list[i] = re.compile(list[i])
        if timeout is not None:
            deadline = _time() + timeout
        with _TelnetSelector() as selector:
            selector.register(self, selectors.EVENT_READ)
            while not self.eof:
                self.process_rawq()
                for i in indices:
                    m = list[i].search(self.cookedq)
                    if m:
                        e = m.end()
                        text = self.cookedq[:e]
                        self.cookedq = self.cookedq[e:]
                        return (i, m, text)
                if timeout is not None:
                    ready = selector.select(timeout)
                    timeout = deadline - _time()
                    if not ready:
                        if timeout < 0:
                            break
                        else:
                            continue
                self.fill_rawq()
        text = self.read_very_lazy()
        if not text and self.eof:
            raise EOFError
        return (-1, None, text)

def __enter__(self):
        return self

def __exit__(self, type, value, traceback):
        self.close()

def test():
    """Test program for telnetlib.

Usage: python telnetlib.py [-d] ... [host [port]]

Default host is localhost; default port is 23.

"""
    debuglevel = 0
    while sys.argv[1:] and sys.argv[1] == '-d':
        debuglevel = debuglevel+1
        del sys.argv[1]
    host = 'localhost'
    if sys.argv[1:]:
        host = sys.argv[1]
    port = 0
    if sys.argv[2:]:
        portstr = sys.argv[2]
        try:
            port = int(portstr)
        except ValueError:
            port = socket.getservbyname(portstr, 'tcp')
    with Telnet() as tn:
        tn.set_debuglevel(debuglevel)
        tn.open(host, port, timeout=0.5)
        tn.interact()

if __name__ == '__main__':
    test()

cmd: