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Linux NoHup fails for Streaming API IG Markets where file is python

This is quite a specific question regarding nohup in linux, which runs a python file.
Back-story, I am trying to save down streaming data (from IG markets broadcast signal). And, as I am trying to run it via a remote-server (so I don't have to keep my own local desktop up 24/7),
somehow, the nohup will not engage when it 'listen's to a broadcast signal.
Below, is the example python code
#!/usr/bin/env python
#-*- coding:utf-8 -*-
"""
IG Markets Stream API sample with Python
"""
user_ = 'xxx'
password_ = 'xxx'
api_key_ = 'xxx' # this is the 1st api key
account_ = 'xxx'
acc_type_ = 'xxx'
fileLoc = 'marketdata_IG_spx_5min.csv'
list_ = ["CHART:IX.D.SPTRD.DAILY.IP:5MINUTE"]
fields_ = ["UTM", "LTV", "TTV", "BID_OPEN", "BID_HIGH", \
"BID_LOW", "BID_CLOSE",]
import time
import sys
import traceback
import logging
import warnings
warnings.filterwarnings('ignore')
from trading_ig import (IGService, IGStreamService)
from trading_ig.lightstreamer import Subscription
cols_ = ['timestamp', 'data']
# A simple function acting as a Subscription listener
def on_prices_update(item_update):
# print("price: %s " % item_update)
print("xxxxxxxx
))
# A simple function acting as a Subscription listener
def on_charts_update(item_update):
# print("price: %s " % item_update)
print(xxxxxx"\
.format(
stock_name=item_update["name"], **item_update["values"]
))
res_ = [xxxxx"\
.format(
stock_name=item_update["name"], **item_update["values"]
).split(' '))]
# display(pd.DataFrame(res_))
try:
data_ = pd.read_csv(fileLoc)[cols_]
data_ = data_.append(pd.DataFrame(res_, columns = cols_))
data_.to_csv(fileLoc)
print('there is data and we are reading it')
# display(data_)
except:
pd.DataFrame(res_, columns = cols_).to_csv(fileLoc)
print('there is no data and we are saving first time')
time.sleep(60) # sleep for 1 min
def main():
logging.basicConfig(level=logging.INFO)
# logging.basicConfig(level=logging.DEBUG)
ig_service = IGService(
user_, password_, api_key_, acc_type_
)
ig_stream_service = IGStreamService(ig_service)
ig_session = ig_stream_service.create_session()
accountId = account_
################ my code to set sleep function to sleep/read at only certain time intervals
s_time = time.time()
############################
# Making a new Subscription in MERGE mode
subscription_prices = Subscription(
mode="MERGE",
# make sure to put L1 in front of the instrument name
items= list_,
fields= fields_
)
# adapter="QUOTE_ADAPTER")
# Adding the "on_price_update" function to Subscription
subscription_prices.addlistener(on_charts_update)
# Registering the Subscription
sub_key_prices = ig_stream_service.ls_client.subscribe(subscription_prices)
print('this is the line here')
input("{0:-^80}\n".format("HIT CR TO UNSUBSCRIBE AND DISCONNECT FROM \
LIGHTSTREAMER"))
# Disconnecting
ig_stream_service.disconnect()
if __name__ == '__main__':
main()
#######
Then, I try to run it on linux using this command : nohup python marketdata.py
where marketdata.py is basically the python code above.
Somehow, the nohup will not engage....... Any experts/guru who might see what I am missing in my code?

How to add configuration setting for sasl.mechanism PLAIN (API) and GSSAPI (Kerberos) authentication in python script

Need some help to set the configuration for sasl.mechanism PLAIN (API) and GSSAPI (Kerberos) authentication.
We are using confluent Kafka here, there are two scripts, one a python script and the second one is a bash script which calls the python one. You can find the script below.
Thanks for the help in advance!
import json
import os
import string
import random
import socket
import uuid
import re
from datetime import datetime
import time
import hashlib
import math
import sys
from functools import cache
from confluent_kafka import Producer, KafkaError, KafkaException
topic_name = os.environ['TOPIC_NAME']
partition_count = int(os.environ['PARTITION_COUNT'])
message_key_template = json.loads(os.environ['KEY_TEMPLATE'])
message_value_template = json.loads(os.environ['VALUE_TEMPLATE'])
message_header_template = json.loads(os.environ['HEADER_TEMPLATE'])
bootstrap_servers = os.environ['BOOTSTRAP_SERVERS']
perf_counter_batch_size = int(os.environ.get('PERF_COUNTER_BATCH_SIZE', 100))
messages_per_aggregate = int(os.environ.get('MESSAGES_PER_AGGREGATE', 1))
max_message_count = int(os.environ.get('MAX_MESSAGE_COUNT', sys.maxsize))
def error_cb(err):
""" The error callback is used for generic client errors. These
errors are generally to be considered informational as the client will
automatically try to recover from all errors, and no extra action
is typically required by the application.
For this example however, we terminate the application if the client
is unable to connect to any broker (_ALL_BROKERS_DOWN) and on
authentication errors (_AUTHENTICATION). """
print("Client error: {}".format(err))
if err.code() == KafkaError._ALL_BROKERS_DOWN or \
err.code() == KafkaError._AUTHENTICATION:
# Any exception raised from this callback will be re-raised from the
# triggering flush() or poll() call.
raise KafkaException(err)
def acked(err, msg):
if err is not None:
print("Failed to send message: %s: %s" % (str(msg), str(err)))
producer_configs = {
'bootstrap.servers': bootstrap_servers,
'client.id': socket.gethostname(),
'error_cb': error_cb
}
# TODO: Need to support sasl.mechanism PLAIN (API) and GSSAPI (Kerberos) authentication.
# TODO: Need to support truststores for connecting to private DCs.
producer = Producer(producer_configs)
# generates a random value if it is not cached in the template_values dictionary
def get_templated_value(term, template_values):
if not term in template_values:
template_values[term] = str(uuid.uuid4())
return template_values[term]
def fill_template_value(value, template_values):
str_value = str(value)
template_regex = '{{(.+?)}}'
templated_terms = re.findall(template_regex, str_value)
for term in templated_terms:
str_value = str_value.replace(f"{{{{{term}}}}}", get_templated_value(term, template_values))
return str_value
def fill_template(template, templated_terms):
# TODO: Need to address metadata field, as it's treated as a string instead of a nested object.
return {field: fill_template_value(value, templated_terms) for field, value in template.items()}
#cache
def get_partition(lock_id):
bits = 128
bucket_size = 2**bits / partition_count
partition = (int(hashlib.md5(lock_id.encode('utf-8')).hexdigest(), 16) / bucket_size)
return math.floor(partition)
sequence_number = int(time.time() * 1000)
sequence_number = 0
message_count = 0
producing = True
start_time = time.perf_counter()
aggregate_message_counter = 0
# cache for templated term values so that they match across the different templates
templated_values = {}
try:
while producing:
sequence_number += 1
aggregate_message_counter += 1
message_count += 1
if aggregate_message_counter % messages_per_aggregate == 0:
# reset templated values
templated_values = {}
else:
for term in list(templated_values):
if term not in ['aggregateId', 'tenantId']:
del(templated_values[term])
# Fill in templated field values
message_key = fill_template(message_key_template, templated_values)
message_value = fill_template(message_value_template, templated_values)
message_header = fill_template(message_header_template, templated_values)
ts = datetime.utcnow().isoformat()[:-3]+'Z'
message_header['timestamp'] = ts
message_header['sequence_number'] = str(sequence_number)
message_value['timestamp'] = ts
message_value['sequenceNumber'] = sequence_number
lock_id = message_header['lock_id']
partition = get_partition(lock_id) # partition by lock_id, since key could be random, but a given aggregate_id should ALWAYS resolve to the same partition, regardless of key.
# Send message
producer.produce(topic_name, partition=partition, key=json.dumps(message_key), value=json.dumps(message_value), headers=message_header, callback=acked)
if sequence_number % perf_counter_batch_size == 0:
producer.flush()
end_time = time.perf_counter()
total_duration = end_time - start_time
messages_per_second=(perf_counter_batch_size/total_duration)
print(f'{messages_per_second} messages/second')
# reset start time
start_time = time.perf_counter()
if message_count >= max_message_count:
break
except Exception as e:
print(f'ERROR: %s' % e)
sys.exit(1)
finally:
producer.flush()

How to invoke C-STORE when trying to query from SCP

I've been using the following code, which is from the pynetdicom library to query and store some images from a remote server SCP, on my machine(SCU).
"""
Query/Retrieve SCU AE example.
This demonstrates a simple application entity that support the Patient
Root Find and Move SOP Classes as SCU. In order to receive retrieved
datasets, this application entity must support the CT Image Storage
SOP Class as SCP as well. For this example to work, there must be an
SCP listening on the specified host and port.
For help on usage,
python qrscu.py -h
"""
import argparse
from netdicom.applicationentity import AE
from netdicom.SOPclass import *
from dicom.dataset import Dataset, FileDataset
from dicom.UID import ExplicitVRLittleEndian, ImplicitVRLittleEndian, \
ExplicitVRBigEndian
import netdicom
# netdicom.debug(True)
import tempfile
# parse commandline
parser = argparse.ArgumentParser(description='storage SCU example')
parser.add_argument('remotehost')
parser.add_argument('remoteport', type=int)
parser.add_argument('searchstring')
parser.add_argument('-p', help='local server port', type=int, default=9999)
parser.add_argument('-aet', help='calling AE title', default='PYNETDICOM')
parser.add_argument('-aec', help='called AE title', default='REMOTESCU')
parser.add_argument('-implicit', action='store_true',
help='negociate implicit transfer syntax only',
default=False)
parser.add_argument('-explicit', action='store_true',
help='negociate explicit transfer syntax only',
default=False)
args = parser.parse_args()
if args.implicit:
ts = [ImplicitVRLittleEndian]
elif args.explicit:
ts = [ExplicitVRLittleEndian]
else:
ts = [
ExplicitVRLittleEndian,
ImplicitVRLittleEndian,
ExplicitVRBigEndian
]
# call back
def OnAssociateResponse(association):
print "Association response received"
def OnAssociateRequest(association):
print "Association resquested"
return True
def OnReceiveStore(SOPClass, DS):
print("FINALLY ENTERED")
print "Received C-STORE", DS.PatientName
try:
# do something with dataset. For instance, store it.
file_meta = Dataset()
file_meta.MediaStorageSOPClassUID = '1.2.840.10008.5.1.4.1.1.2'
# !! Need valid UID here
file_meta.MediaStorageSOPInstanceUID = "1.2.3"
# !!! Need valid UIDs here
file_meta.ImplementationClassUID = "1.2.3.4"
filename = '%s/%s.dcm' % (tempfile.gettempdir(), DS.SOPInstanceUID)
ds = FileDataset(filename, {},
file_meta=file_meta, preamble="\0" * 128)
ds.update(DS)
#ds.is_little_endian = True
#ds.is_implicit_VR = True
ds.save_as(filename)
print "File %s written" % filename
except:
pass
# must return appropriate status
return SOPClass.Success
# create application entity
MyAE = AE(args.aet, args.p, [PatientRootFindSOPClass,
PatientRootMoveSOPClass,
VerificationSOPClass], [StorageSOPClass], ts)
MyAE.OnAssociateResponse = OnAssociateResponse
MyAE.OnAssociateRequest = OnAssociateRequest
MyAE.OnReceiveStore = OnReceiveStore
MyAE.start()
# remote application entity
RemoteAE = dict(Address=args.remotehost, Port=args.remoteport, AET=args.aec)
# create association with remote AE
print "Request association"
assoc = MyAE.RequestAssociation(RemoteAE)
# perform a DICOM ECHO
print "DICOM Echo ... ",
st = assoc.VerificationSOPClass.SCU(1)
print 'done with status "%s"' % st
print "DICOM FindSCU ... ",
d = Dataset()
d.PatientsName = args.searchstring
d.QueryRetrieveLevel = "PATIENT"
d.PatientID = "*"
st = assoc.PatientRootFindSOPClass.SCU(d, 1)
print 'done with status "%s"' % st
for ss in st:
if not ss[1]:
continue
# print ss[1]
try:
d.PatientID = ss[1].PatientID
except:
continue
print "Moving"
print d
assoc2 = MyAE.RequestAssociation(RemoteAE)
gen = assoc2.PatientRootMoveSOPClass.SCU(d, 'SAMTEST', 1)
for gg in gen:
print
print gg
assoc2.Release(0)
print "QWEQWE"
print "Release association"
assoc.Release(0)
# done
MyAE.Quit()
Running the program, I get the following output:
Request association
Association response received
DICOM Echo ... done with status "Success "
DICOM FindSCU ... done with status "<generator object SCU at 0x106014c30>"
Moving
(0008, 0052) Query/Retrieve Level CS: 'PATIENT'
(0010, 0010) Patient's Name PN: 'P*'
(0010, 0020) Patient ID LO: 'Pat00001563'
Association response received
QWEQWE
Moving
(0008, 0052) Query/Retrieve Level CS: 'PATIENT'
(0010, 0010) Patient's Name PN: 'P*'
(0010, 0020) Patient ID LO: 'Pat00002021'
Association response received
QWEQWE
Release association
Echo works so I know my associations are working and I am able to query and see the files on the server as suggested by the output. As you can see however, OnReceiveStore does not seem to be called. I am pretty new to DICOM and I was wondering what might be the case. Correct me if I am wrong but I think the line gen = assoc2.PatientRootMoveSOPClass.SCU(d, 'SAMTEST', 1) is supposed to invoke OnReceiveStore. If not, some insight on how C-STORE should be called is appreciated.

DICOM C-MOVE is a complicated operation, if You are not very familiar with DICOM.
You are not calling OnReceiveStore Yourself, it's called when the SCP starts sending instances to Your application. You issue a C-MOVE command to the SCP with Your own AE title, where You want to receive the images. In Your case SAMTEST. Since this is the only parameter for the C-MOVE command, then the SCP needs to be configured before-hand to know the IP and port of the SAMTEST AE. Have You done this?
I don't know, why the code is not outputting responses from the SCP to the C-MOVE command. It looks like it should. These could give a good indication, what is happening. You can also check the logs on the SCP side, to see, what's happening.
Also, here is some quite good reading about C-MOVE operation.

Python - Get Path of Selected File in Current Windows Explorer

I am trying to do this in Python 2.7. I have found an answer for it in C# here, but I am having trouble recreating it in Python. The answer suggested here does explain the concept which I understand, but I have no idea how to get it going.
Basically I just want to mark a file, press Winkey+C and have its path copied. I know how to do the hotkey part (pyhk, win32 [RegisterHotKey]), but my trouble is working around with the filepath.
Thanks in advance!

it takes a lot of hacking around, but a rough solution is below:
#!python3
import win32gui, time
from win32con import PAGE_READWRITE, MEM_COMMIT, MEM_RESERVE, MEM_RELEASE, PROCESS_ALL_ACCESS, WM_GETTEXTLENGTH, WM_GETTEXT
from commctrl import LVM_GETITEMTEXT, LVM_GETITEMCOUNT, LVM_GETNEXTITEM, LVNI_SELECTED
import os
import struct
import ctypes
import win32api
GetWindowThreadProcessId = ctypes.windll.user32.GetWindowThreadProcessId
VirtualAllocEx = ctypes.windll.kernel32.VirtualAllocEx
VirtualFreeEx = ctypes.windll.kernel32.VirtualFreeEx
OpenProcess = ctypes.windll.kernel32.OpenProcess
WriteProcessMemory = ctypes.windll.kernel32.WriteProcessMemory
ReadProcessMemory = ctypes.windll.kernel32.ReadProcessMemory
memcpy = ctypes.cdll.msvcrt.memcpy
def readListViewItems(hwnd, column_index=0):
# Allocate virtual memory inside target process
pid = ctypes.create_string_buffer(4)
p_pid = ctypes.addressof(pid)
GetWindowThreadProcessId(hwnd, p_pid) # process owning the given hwnd
hProcHnd = OpenProcess(PROCESS_ALL_ACCESS, False, struct.unpack("i",pid)[0])
pLVI = VirtualAllocEx(hProcHnd, 0, 4096, MEM_RESERVE|MEM_COMMIT, PAGE_READWRITE)
pBuffer = VirtualAllocEx(hProcHnd, 0, 4096, MEM_RESERVE|MEM_COMMIT, PAGE_READWRITE)
# Prepare an LVITEM record and write it to target process memory
lvitem_str = struct.pack('iiiiiiiii', *[0,0,column_index,0,0,pBuffer,4096,0,0])
lvitem_buffer = ctypes.create_string_buffer(lvitem_str)
copied = ctypes.create_string_buffer(4)
p_copied = ctypes.addressof(copied)
WriteProcessMemory(hProcHnd, pLVI, ctypes.addressof(lvitem_buffer), ctypes.sizeof(lvitem_buffer), p_copied)
# iterate items in the SysListView32 control
num_items = win32gui.SendMessage(hwnd, LVM_GETITEMCOUNT)
item_texts = []
for item_index in range(num_items):
win32gui.SendMessage(hwnd, LVM_GETITEMTEXT, item_index, pLVI)
target_buff = ctypes.create_string_buffer(4096)
ReadProcessMemory(hProcHnd, pBuffer, ctypes.addressof(target_buff), 4096, p_copied)
item_texts.append(target_buff.value)
VirtualFreeEx(hProcHnd, pBuffer, 0, MEM_RELEASE)
VirtualFreeEx(hProcHnd, pLVI, 0, MEM_RELEASE)
win32api.CloseHandle(hProcHnd)
return item_texts
def getSelectedListViewItem(hwnd):
return win32gui.SendMessage(hwnd, LVM_GETNEXTITEM, -1, LVNI_SELECTED)
def getSelectedListViewItems(hwnd):
items = []
item = -1
while True:
item = win32gui.SendMessage(hwnd, LVM_GETNEXTITEM, item, LVNI_SELECTED)
if item == -1:
break
items.append(item)
return items
def getEditText(hwnd):
# api returns 16 bit characters so buffer needs 1 more char for null and twice the num of chars
buf_size = (win32gui.SendMessage(hwnd, WM_GETTEXTLENGTH, 0, 0) +1 ) * 2
target_buff = ctypes.create_string_buffer(buf_size)
win32gui.SendMessage(hwnd, WM_GETTEXT, buf_size, ctypes.addressof(target_buff))
return target_buff.raw.decode('utf16')[:-1]# remove the null char on the end
def _normaliseText(controlText):
'''Remove '&' characters, and lower case.
Useful for matching control text.'''
return controlText.lower().replace('&', '')
def _windowEnumerationHandler(hwnd, resultList):
'''Pass to win32gui.EnumWindows() to generate list of window handle,
window text, window class tuples.'''
resultList.append((hwnd, win32gui.GetWindowText(hwnd), win32gui.GetClassName(hwnd)))
def searchChildWindows(currentHwnd,
wantedText=None,
wantedClass=None,
selectionFunction=None):
results = []
childWindows = []
try:
win32gui.EnumChildWindows(currentHwnd,
_windowEnumerationHandler,
childWindows)
except win32gui.error:
# This seems to mean that the control *cannot* have child windows,
# i.e. not a container.
return
for childHwnd, windowText, windowClass in childWindows:
descendentMatchingHwnds = searchChildWindows(childHwnd)
if descendentMatchingHwnds:
results += descendentMatchingHwnds
if wantedText and \
not _normaliseText(wantedText) in _normaliseText(windowText):
continue
if wantedClass and \
not windowClass == wantedClass:
continue
if selectionFunction and \
not selectionFunction(childHwnd):
continue
results.append(childHwnd)
return results
w=win32gui
while True:
time.sleep(5)
window = w.GetForegroundWindow()
print("window: %s" % window)
if (window != 0):
if (w.GetClassName(window) == 'CabinetWClass'): # the main explorer window
print("class: %s" % w.GetClassName(window))
print("text: %s " %w.GetWindowText(window))
children = list(set(searchChildWindows(window)))
addr_edit = None
file_view = None
for child in children:
if (w.GetClassName(child) == 'ComboBoxEx32'): # the address bar
addr_children = list(set(searchChildWindows(child)))
for addr_child in addr_children:
if (w.GetClassName(addr_child) == 'Edit'):
addr_edit = addr_child
pass
elif (w.GetClassName(child) == 'SysListView32'): # the list control within the window that shows the files
file_view = child
if addr_edit:
path = getEditText(addr_edit)
else:
print('something went wrong - no address bar found')
path = ''
if file_view:
files = [item.decode('utf8') for item in readListViewItems(file_view)]
indexes = getSelectedListViewItems(file_view)
print('path: %s' % path)
print('files: %s' % files)
print('selected files:')
for index in indexes:
print("\t%s - %s" % (files[index], os.path.join(path, files[index])))
else:
print('something went wrong - no file view found')
so what this does is keep checking if the active window is of the class the explorer window uses, then iterates through the children widgets to find the address bar and the file list view. Then it extracts the list of files from the listview and requests the selected indexes. it also gets and decodes the text from the address bar.
at the bottom the info is then combined to give you the complete path, the folder path, the file name or any combination thereof.
I have tested this on windows xp with python3.4, but you will need to install the win32gui and win32 conn packages.

# Import Statement.
import subprocess
# Trigger subprocess.
subprocess.popen(r'explorer /select,"C:\path\of\folder\file"'

Alternative to tuntap

I'm trying to transmit TCP/IP over a radio that is connected to my computer (specifically, the USRP). Right now, it's done very simply using Tun/Tap to set up a new network interface. Here's the code:
from gnuradio import gr, gru, modulation_utils
from gnuradio import usrp
from gnuradio import eng_notation
from gnuradio.eng_option import eng_option
from optparse import OptionParser
import random
import time
import struct
import sys
import os
# from current dir
from transmit_path import transmit_path
from receive_path import receive_path
import fusb_options
#print os.getpid()
#raw_input('Attach and press enter')
# Linux specific...
# TUNSETIFF ifr flags from <linux/tun_if.h>
IFF_TUN = 0x0001 # tunnel IP packets
IFF_TAP = 0x0002 # tunnel ethernet frames
IFF_NO_PI = 0x1000 # don't pass extra packet info
IFF_ONE_QUEUE = 0x2000 # beats me ;)
def open_tun_interface(tun_device_filename):
from fcntl import ioctl
mode = IFF_TAP | IFF_NO_PI
TUNSETIFF = 0x400454ca
tun = os.open(tun_device_filename, os.O_RDWR)
ifs = ioctl(tun, TUNSETIFF, struct.pack("16sH", "gr%d", mode))
ifname = ifs[:16].strip("\x00")
return (tun, ifname)
# /////////////////////////////////////////////////////////////////////////////
# the flow graph
# /////////////////////////////////////////////////////////////////////////////
class my_top_block(gr.top_block):
def __init__(self, mod_class, demod_class,
rx_callback, options):
gr.top_block.__init__(self)
self.txpath = transmit_path(mod_class, options)
self.rxpath = receive_path(demod_class, rx_callback, options)
self.connect(self.txpath);
self.connect(self.rxpath);
def send_pkt(self, payload='', eof=False):
return self.txpath.send_pkt(payload, eof)
def carrier_sensed(self):
"""
Return True if the receive path thinks there's carrier
"""
return self.rxpath.carrier_sensed()
# /////////////////////////////////////////////////////////////////////////////
# Carrier Sense MAC
# /////////////////////////////////////////////////////////////////////////////
class cs_mac(object):
"""
Prototype carrier sense MAC
Reads packets from the TUN/TAP interface, and sends them to the PHY.
Receives packets from the PHY via phy_rx_callback, and sends them
into the TUN/TAP interface.
Of course, we're not restricted to getting packets via TUN/TAP, this
is just an example.
"""
def __init__(self, tun_fd, verbose=False):
self.tun_fd = tun_fd # file descriptor for TUN/TAP interface
self.verbose = verbose
self.tb = None # top block (access to PHY)
def set_top_block(self, tb):
self.tb = tb
def phy_rx_callback(self, ok, payload):
"""
Invoked by thread associated with PHY to pass received packet up.
#param ok: bool indicating whether payload CRC was OK
#param payload: contents of the packet (string)
"""
if self.verbose:
print "Rx: ok = %r len(payload) = %4d" % (ok, len(payload))
if ok:
os.write(self.tun_fd, payload)
def main_loop(self):
"""
Main loop for MAC.
Only returns if we get an error reading from TUN.
FIXME: may want to check for EINTR and EAGAIN and reissue read
"""
min_delay = 0.001 # seconds
while 1:
payload = os.read(self.tun_fd, 10*1024)
if not payload:
self.tb.send_pkt(eof=True)
break
if self.verbose:
print "Tx: len(payload) = %4d" % (len(payload),)
delay = min_delay
while self.tb.carrier_sensed():
sys.stderr.write('B')
time.sleep(delay)
if delay < 0.050:
delay = delay * 2 # exponential back-off
self.tb.send_pkt(payload)
# /////////////////////////////////////////////////////////////////////////////
# main
# /////////////////////////////////////////////////////////////////////////////
def main():
mods = modulation_utils.type_1_mods()
demods = modulation_utils.type_1_demods()
parser = OptionParser (option_class=eng_option, conflict_handler="resolve")
expert_grp = parser.add_option_group("Expert")
parser.add_option("-m", "--modulation", type="choice", choices=mods.keys(),
default='gmsk',
help="Select modulation from: %s [default=%%default]"
% (', '.join(mods.keys()),))
parser.add_option("-v","--verbose", action="store_true", default=False)
expert_grp.add_option("-c", "--carrier-threshold", type="eng_float", default=30,
help="set carrier detect threshold (dB) [default=%default]")
expert_grp.add_option("","--tun-device-filename", default="/dev/net/tun",
help="path to tun device file [default=%default]")
transmit_path.add_options(parser, expert_grp)
receive_path.add_options(parser, expert_grp)
for mod in mods.values():
mod.add_options(expert_grp)
for demod in demods.values():
demod.add_options(expert_grp)
fusb_options.add_options(expert_grp)
(options, args) = parser.parse_args ()
if len(args) != 0:
parser.print_help(sys.stderr)
sys.exit(1)
if options.rx_freq is None or options.tx_freq is None:
sys.stderr.write("You must specify -f FREQ or --freq FREQ\n")
parser.print_help(sys.stderr)
sys.exit(1)
# open the TUN/TAP interface
(tun_fd, tun_ifname) = open_tun_interface(options.tun_device_filename)
# Attempt to enable realtime scheduling
r = gr.enable_realtime_scheduling()
if r == gr.RT_OK:
realtime = True
else:
realtime = False
print "Note: failed to enable realtime scheduling"
# If the user hasn't set the fusb_* parameters on the command line,
# pick some values that will reduce latency.
if options.fusb_block_size == 0 and options.fusb_nblocks == 0:
if realtime: # be more aggressive
options.fusb_block_size = gr.prefs().get_long('fusb', 'rt_block_size', 1024)
options.fusb_nblocks = gr.prefs().get_long('fusb', 'rt_nblocks', 16)
else:
options.fusb_block_size = gr.prefs().get_long('fusb', 'block_size', 4096)
options.fusb_nblocks = gr.prefs().get_long('fusb', 'nblocks', 16)
#print "fusb_block_size =", options.fusb_block_size
#print "fusb_nblocks =", options.fusb_nblocks
# instantiate the MAC
mac = cs_mac(tun_fd, verbose=True)
# build the graph (PHY)
tb = my_top_block(mods[options.modulation],
demods[options.modulation],
mac.phy_rx_callback,
options)
mac.set_top_block(tb) # give the MAC a handle for the PHY
if tb.txpath.bitrate() != tb.rxpath.bitrate():
print "WARNING: Transmit bitrate = %sb/sec, Receive bitrate = %sb/sec" % (
eng_notation.num_to_str(tb.txpath.bitrate()),
eng_notation.num_to_str(tb.rxpath.bitrate()))
print "modulation: %s" % (options.modulation,)
print "freq: %s" % (eng_notation.num_to_str(options.tx_freq))
print "bitrate: %sb/sec" % (eng_notation.num_to_str(tb.txpath.bitrate()),)
print "samples/symbol: %3d" % (tb.txpath.samples_per_symbol(),)
#print "interp: %3d" % (tb.txpath.interp(),)
#print "decim: %3d" % (tb.rxpath.decim(),)
tb.rxpath.set_carrier_threshold(options.carrier_threshold)
print "Carrier sense threshold:", options.carrier_threshold, "dB"
print
print "Allocated virtual ethernet interface: %s" % (tun_ifname,)
print "You must now use ifconfig to set its IP address. E.g.,"
print
print " $ sudo ifconfig %s 192.168.200.1" % (tun_ifname,)
print
print "Be sure to use a different address in the same subnet for each machine."
print
tb.start() # Start executing the flow graph (runs in separate threads)
mac.main_loop() # don't expect this to return...
tb.stop() # but if it does, tell flow graph to stop.
tb.wait() # wait for it to finish
if __name__ == '__main__':
try:
main()
except KeyboardInterrupt:
pass
(Anyone familiar with GNU Radio will recognize this as tunnel.py)
My question is, is there a better way to move packets to and from the kernel than tun/tap? I've been looking at ipip or maybe using sockets, but I'm pretty sure those won't be very fast. Speed is what I'm most concerned with.

Remember that tunnel.py is a really, really rough example, and hasn't been updated in a while. It's not really meant to be a basis for other code, so be careful of how much you rely on the code.
Also, remember that TCP over unreliable radio links has significant issues:
http://en.wikipedia.org/wiki/Transmission_Control_Protocol#TCP_over_wireless_networks