Wikipedia:Reference desk/Archives/Computing/2012 July 23

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July 23

HTTPS

Is there a way to make Firefox use https instead of http, and is there any point? — Fly by Night (talk) 01:41, 23 July 2012 (UTC)

There is an extension/plugin you can use with Firefox (https everywhere) to get HTTPS by default. The article at HTTPS has a link to it, and an explanation of why you might want it. RudolfRed (talk) 01:57, 23 July 2012 (UTC)

I don't think you can use https unless the server you're contacting is prepared to handle the https protocol, though. Most are not. There are tricks for securing parts of the pathway, but you can't secure the whole pathway unless the server is secure. Looie496 (talk) 02:15, 23 July 2012 (UTC)

Upgrading a TOSHIBA Satellite A215

A friend has the above mentioned laptop, and the ATI Radeon X1200 Series graphics card. They are unable to play the game Borderlands, because this card will not support Cell Shader 3.0. According to this, someone else who has the same model and wanted to upgrade their graphics card can not. Is this true? Are there any options out there? and decently priced i hope, perhaps around $60 that fit in the laptop, work with what slots it has, and can run borderlands?

Thanks for the help!

74.117.245.62 (talk) 07:47, 23 July 2012 (UTC)

The usual answer is no; the graphics card fitted inside your laptop is one thing you cannot upgrade. And a search seems to confirm this. For example, the first post on this forum from 2006 seems pretty emphatic. However, a very small number of laptops do support upgradable graphics cards, but I'm afraid the rather old Toshiba A215 almost certainly isn't one of them. That said, maybe this article has a possible, though rather expensive solution. For the $330 or more price tag (and that was in 2008 prices) you might be better off getting a new laptop or buying a cheap but better specified desktop machine just for playing games. Astronaut (talk) 16:48, 24 July 2012 (UTC)

Microsoft Research autobiography tool

I read somewhere that Microsoft Research has (probably within the last few months) released a tool that can be used to generate an autobiographical timeline from e-mail records etc. What's it called? NeonMerlin 10:24, 23 July 2012 (UTC)

Perhaps you are looking for the Microsoft Research LifeBrowser? The Verge has links to more sources. --Kushal (talk) 20:55, 24 July 2012 (UTC)

about live chat for website

how can insert a live chat box on a webpage?? — Preceding unsigned comment added by 59.178.144.3 (talk) 13:24, 23 July 2012 (UTC)

Well.. it depends on what kind of chatbox, you want.. Do you want to host the chatbox? — Preceding unsigned comment added by 65.49.68.173 (talk) 15:12, 23 July 2012 (UTC)

Googling live chat widget gives a lot of results, though I can't personally recommend any. --Colapeninsula (talk) 08:20, 24 July 2012 (UTC)

Same MAC

If someone changes the MAC of his computer and uses the same as an AP or other computer of a WLAN network, would he be disrupting this network (even if he's not logged on it)? If no, how does the network ignores him? If possible, WLANs would be pretty susceptible to disturbance. OsmanRF34 (talk) 13:36, 23 July 2012 (UTC)

Yes, it's very disruptive. An ethernet switch remembers to which of its ports a given MAC wired, and only sends traffic for that device out to that port (ref Radia Perlman Interconnections). Most modern OSes will notice if another station uses the same MAC as they do, and will alert the user, and managed switches can report likewise. I don't know about WLAN. There is no shortage of easy ways to disrupt a WLAN. -- Finlay McWalterჷTalk 14:21, 23 July 2012 (UTC)

Do you mean that there are lots of way of jamming a WLAN without extra jamming devices? I really mean, is that simple that someone sits with his laptop somewhere, fakes his MAC and a network near him is disrupted? OsmanRF34 (talk) 17:16, 23 July 2012 (UTC)

Yes, it's that easy. Because WLAN works as one big hub though, it might actually still work for each client. You'd have some weird effects though. This would depend on the OS of the router mostly. What Finlay's referring to are other attacks that are entirely software based... like sending REAUTH notices, or the Wifi equivalent of JAM signals... which can disrupt everyone on the network segment. Shadowjams (talk) 21:22, 23 July 2012 (UTC)

Hexadecimal objects at python

In python something like this

import os
print os.walk

outputs <function walk at 0x004D2DB0>

What 0x004D2DB0 means? 65.49.68.173 (talk) 19:12, 23 July 2012 (UTC)

You're printing the value of the function pointer to Python's os.walk utility function. That is not the same as executing the function. Nimur (talk) 19:26, 23 July 2012 (UTC)

(ec)When you try to print anything in Python, the runtime has to ask that thing to produce a string representation of itself. For objects (and other things) those override the __str__() method, and they return whatever their designer thought appropriate. But other things aren't defined in Python, but are created by the python runtime system itself. Different python implementations might chose subtly different ways of printing those. In the case of functions, the cpython system (which is what you're calling python, as its the most common python runtime) prints a hexadecimal string, as you've observed. I don't think they make any claim about that string, other than its unique to that function (at this exact moment in time); there's nothing you can meaningfully do with it (until you get to some pretty advanced coding) - it's a little implementation detail leaking through, and one you can safely ignore. Just for comparison, on my 64 bit linux system, in cpython your code prints:

 <function walk at 0x7f23cb643cf8>

but in pypy (a different python runtime system) it prints:

 <function walk at 0x00007f01699e6f98>

What it's actually doing (probably) is printing the address in the cpython process's memory into which that function has been loaded. -- Finlay McWalterჷTalk 19:27, 23 July 2012 (UTC)

A good illustration of why there numbers aren't necessarily "pointers" is this code:

     def a(): return
     def b(): return
     def c(): return
     print a,b,c

If I run this on cpython or pypy the values clearly are pointers (they're 120 apart from one another). But on jython, another python implementation, the result is very different:

 <function a at 0x1> <function b at 0x2> <function c at 0x3>

So obviously on that implementation they're just indices into some internal table. So the moral of the story is "it's just a magic number; don't worry about it". -- Finlay McWalterჷTalk 22:04, 23 July 2012 (UTC)

If the intention when using "print" was to get information on the function, try:

help(os.walk)

instead. You might also find:

dir(os)

useful to list the functions in a module.

help(os)

is also useful but much more verbose than the dir command.-gadfium 22:36, 23 July 2012 (UTC)