473,544 Members | 2,219 Online
Bytes | Software Development & Data Engineering Community
+ Post

Home Posts Topics Members FAQ

Cross-platform socket.getsocko pt and struct.unpack (or socket timeout)?

M2Crypto has some old code that gets and sets socket timeouts in
for example:

def get_socket_read _timeout(self):
timeout.struct_ to_timeout(self .socket.getsock opt(socket.SOL_ SOCKET,
socket.SO_RCVTI MEO, timeout.struct_ size()))

The helper timeout module is here:

I just noticed that this does not work on Windows. Here's a small test
program that demonstrates the issue using native and Cygwin Python
2.5.2, 32-bit Windows XP (no M2Crypto needed for this):

import struct
import socket

s = socket.socket(s ocket.AF_INET, socket.SOCK_STR EAM)
s.setsockopt(so cket.SOL_SOCKET , socket.SO_REUSE ADDR, 1)
timeout_struct = s.getsockopt(so cket.SOL_SOCKET , socket.SO_RCVTI MEO,
struct.calcsize ('ll'))
print "%d:'%s'" % (len(timeout_st ruct), timeout_struct)
print struct.unpack(' ll', timeout_struct)

This outputs

4:' '
Traceback (most recent call last):
File "t.py", line 8, in <module>
print struct.unpack(' ll', timeout_struct)
File "/usr/lib/python2.5/struct.py", line 87, in unpack
return o.unpack(s)
struct.error: unpack requires a string argument of length 8

It works fine on 32 and 64 bit Linux (Ubuntu 8.04).

The kicker is that I can't remember if I actually ever tested this on
Windows before.

This goes to a level of socket programming that I haven't done before.

Is there a cross-platform way of doing what the M2Crypto code is
attempting to do?

Heikki Toivonen
Sep 16 '08 #1
2 3523
Heikki Toivonen wrote:
Is there a cross-platform way of doing what the M2Crypto code is
attempting to do?
calling the socket object's settimeout() method?


Sep 16 '08 #2
Fredrik Lundh wrote:
Heikki Toivonen wrote:
>Is there a cross-platform way of doing what the M2Crypto code is
attempting to do?

calling the socket object's settimeout() method?
I would suspect that is not strictly equivalent to what the old code is
doing, though, because it seems you can set read and write timeouts
separately using the socket options directly.

Heikki Toivonen
Sep 16 '08 #3

This thread has been closed and replies have been disabled. Please start a new discussion.

Similar topics

by: Matthew Barnes | last post by:
I was wondering if there would be any interest in extending the struct.unpack format notation to be able to express groups of data with parenthesis. For example: >>> data = struct.pack('iiii', 1, 2, 3, 4) >>> struct.unpack('i(ii)i', data) # Note the parentheses (1, (2, 3), 4)
by: Geoffrey | last post by:
Hope someone can help. I am trying to read data from a file binary file and then unpack the data into python variables. Some of the data is store like this; xbuffer: '\x00\x00\xb9\x02\x13EXCLUDE_CREDIT_CARD' # the above was printed using repr(xbuffer). # Note that int(0x13) = 19 which is exactly the length of the visible text #
by: grant | last post by:
Hi All, I am pretty new to python and am having a problem intepreting binary data using struct.unpack. I am reading a file containing binary packed data using open with "rb". All the values are coming through fine when using (integer1,) = struct.unpack('l', line) except when line contains "carriage-return" "linefeed" which are valid...
by: g.franzkowiak | last post by:
Hello Everybody, I've read a pipe and store it in a object. My next step was the separation from 4 bytes with obj = string.join(list(dataObject) ==> '\x16 \x00 \x00 \x00' and the converting by value = struct.unpack('I', obj) generated the error "unpack str size does not match format" Unfortunately is len(obj) 7, but integer lengt 4.
by: Eric Jacoboni | last post by:
Hi, To experiment with unpacking, i've written a little C code which stores one record in a file. Then, i try to reread this file to unpack the record. Here's the struct of a record: typedef struct { char nom;
by: Pieter Rautenbach | last post by:
Hallo, I have a 64 bit server with CentOS 4.3 installed, running Python. $ uname -a Linux lutetium.mxit.co.za 2.6.9-34.ELsmp #1 SMP Thu Mar 9 06:23:23 GMT 2006 x86_64 x86_64 x86_64 GNU/Linux Consider the following two snippets, issuing a struct.unpack(...) using Python 2.3.4 and Python 2.5 respectively.
by: OhKyu Yoon | last post by:
Hi! I have a really long binary file that I want to read. The way I am doing it now is: for i in xrange(N): # N is about 10,000,000 time = struct.unpack('=HHHH', infile.read(8)) # do something tdc = struct.unpack('=LiLiLiLi',self.lmf.read(32)) # do something
by: brnstrmrs | last post by:
If I run: testValue = '\x02\x00' junk = struct.unpack('h', testValue) Everything works but If I run testValue = raw_input("Enter Binary Code..:") inputting at the console '\x02\x00' junk = struct.unpack('h', testValue)
by: Ping Zhao | last post by:
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi, I am writing a small program to decode MS bitmap image. When I use statements as follow, it works fine: header = str(struct.unpack('2s', self.__read(src, 2))) header = int(struct.unpack('1i', self.__read(src, 4)))
by: marktang | last post by:
ONU (Optical Network Unit) is one of the key components for providing high-speed Internet services. Its primary function is to act as an endpoint device located at the user's premises. However, people are often confused as to whether an ONU can Work As a Router. In this blog post, we’ll explore What is ONU, What Is Router, ONU & Router’s main...
by: Hystou | last post by:
Most computers default to English, but sometimes we require a different language, especially when relocating. Forgot to request a specific language before your computer shipped? No problem! You can effortlessly switch the default language on Windows 10 without reinstalling. I'll walk you through it. First, let's disable language...
by: jinu1996 | last post by:
In today's digital age, having a compelling online presence is paramount for businesses aiming to thrive in a competitive landscape. At the heart of this digital strategy lies an intricately woven tapestry of website design and digital marketing. It's not merely about having a website; it's about crafting an immersive digital experience that...
by: tracyyun | last post by:
Dear forum friends, With the development of smart home technology, a variety of wireless communication protocols have appeared on the market, such as Zigbee, Z-Wave, Wi-Fi, Bluetooth, etc. Each protocol has its own unique characteristics and advantages, but as a user who is planning to build a smart home system, I am a bit confused by the...
by: isladogs | last post by:
The next Access Europe User Group meeting will be on Wednesday 1 May 2024 starting at 18:00 UK time (6PM UTC+1) and finishing by 19:30 (7.30PM). In this session, we are pleased to welcome a new presenter, Adolph Dupré who will be discussing some powerful techniques for using class modules. He will explain when you may want to use classes...
by: conductexam | last post by:
I have .net C# application in which I am extracting data from word file and save it in database particularly. To store word all data as it is I am converting the whole word file firstly in HTML and then checking html paragraph one by one. At the time of converting from word file to html my equations which are in the word document file was convert...
by: TSSRALBI | last post by:
Hello I'm a network technician in training and I need your help. I am currently learning how to create and manage the different types of VPNs and I have a question about LAN-to-LAN VPNs. The last exercise I practiced was to create a LAN-to-LAN VPN between two Pfsense firewalls, by using IPSEC protocols. I succeeded, with both firewalls in...
by: adsilva | last post by:
A Windows Forms form does not have the event Unload, like VB6. What one acts like?
by: muto222 | last post by:
How can i add a mobile payment intergratation into php mysql website.

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.