Wikipedia:Reference desk/Archives/Computing/2014 January 14

= January 14 =

Sorting threads in a Facebook secret group
In my normal view of Facebook there's a little "SORT" button I can click to see my threads in two different orders, Top Stories, or Most Recent. I'm a member (admin actually) of a Facebook Secret Group, and there appears to be no such option when I have that Group's page open. Facebook displays threads in a quite inconvenient (to me) order. Currently the top thread is one that has had no activity since 1 November. I want to be able to have the most recently active thread on top.

Anyone got any ideas? HiLo48 (talk) 07:16, 14 January 2014 (UTC)
 * Is the top thread pinned? In my experience, group threads have always been ordered by most recent unless someone pins a thread to the top. It's not always entirely obvious on the desktop site (though I'm at work and can't check), but viewing on mobile will collapse the pinned threads and show "View (X) pinned post(s)", making it reasonably clear that there is one. MChesterMC (talk) 09:56, 14 January 2014 (UTC)
 * Hey, thanks for that tip. It wasn't pinned, but now I've pinned the one I want at the top. Excellent. (Still no idea how Facebook was deciding on the previous order.) HiLo48 (talk) 11:09, 14 January 2014 (UTC)

"lisp macro" "lisp script" ?
Why do they call "Lisp macros" not "Lisp scripts"? Is there any difference? Couldn't we also say "Python macros" instead of "Python scripts? Or in the same way, Perl macros/scripts?OsmanRF34 (talk) 12:47, 14 January 2014 (UTC)


 * I believe it's mainly for historical reasons. Lisp was around very early in the history of programming languages when the idea of a "scripting language" hadn't really developed.  Lisp did come to be very popular as a scripting language for EMACS - which was an exceedingly popular tool of the time - but back then, you'd think of these as "editor macros" where the effect of a single keystroke command is converted via a "macro" into a larger set of commands.   (Macro (computer science) defines the term as "a rule or pattern that specifies how a certain input sequence (often a sequence of characters) should be mapped to a replacement output sequence (also often a sequence of characters) according to a defined procedure." - which is exactly the role of Lisp in EMACS).  So calling them "Lisp macros" made some kind of sense to distinguish them from "Lisp programs" which were full-up stand-alone programs (typically in AI applications).   Nowadays, we think more of tools like EMACS as having scripting capabilities - so the nomenclature has changed over time.  I guess Lisp is just a little behind the times. SteveBaker (talk) 13:46, 14 January 2014 (UTC)


 * The bit about keyboard macros is not the part of that page relevant to Lisp! Lisp macros are a particular feature within the language (it is the one that perhaps provides the most of the power for which Lisp is famous), and no Lisper would refer to an entire program (or module) as a macro.  --Tardis (talk) 01:48, 16 January 2014 (UTC)

Samsung Galaxy S4 / Android warning messages
I recently bought a new Samsung Galaxy S4 phone. Mostly I really like it but there's one bit of functionality I find annoying. I'm not sure whether this is S4 specific - I suspect it may be standard Android functionality.

I don't tend to keep Mobile Data switched on unless I'm actually using it for something, which means I might turn it on and off several times I day. Whenever I switch it on, I get a warning message: "Connecting via packet data may incur additional charges. Continue?" When I switch it off I get another message: "Disable mobile data connection?" It's only one extra tap on "OK" each time, but it seems unnecessary to prompt me always as to whether I want to do the thing I've just said I want to do. Is there any way to turn off these messages? --OpenToppedBus - Talk to the driver 13:48, 14 January 2014 (UTC)


 * Tried it on my Galaxy Core (Android 4.2.1); the first time it asked me 'Are you sure', and there was a checkbox 'Always ask me', which I uncheked. It never nagged me again. — Edokter  ( talk ) — 14:03, 14 January 2014 (UTC)


 * Tried it on my Samsung Stellar (Android 4.1.2). I get the same message after turning data off (with no check box) and I don't get any message turning it on.  Dismas |(talk) 14:27, 14 January 2014 (UTC)


 * Are you going through your Settings screen? I turn mine off/on by dragging down the top bar and then tapping the Mobile Data icon. — Edokter  ( talk ) — 15:48, 14 January 2014 (UTC)
 * Same phone as the questioner (Android 4.3), same behaviour (though not an issue for me since I keep the mobile data on). No checkboxes. The popup only appears when turning off via settings, on or off via the power button menu. I don't get a popup if I change it (either way) via the quick settings bar on the notification screen, which seems to be different to what Edokter is experiencing.  — Preceding unsigned comment added by MChesterMC (talk • contribs) 10:49, 16 January 2014 (UTC)


 * That is how I see it too. — Edokter  ( talk ) — 16:56, 17 January 2014 (UTC)


 * Interesting on my Android 4.3 Samsung S3 I get the warning with a tick box when I use the button up in the status area, but I get the warning without the tick-box if I go through the settings menu.
 * OpenToppedBus, are you using the quick buttons in the status area? Or going through settings?
 * If all else fails, you could probably download any one of a number of desktop widgets that would sit on your desktop and toggle mobile data that way. APL (talk) 23:53, 17 January 2014 (UTC)

Computer--Router--Cable Modem--Internet; Whose DNS settings get used?
I was reading about using Google Public DNS here and was wondering, if the machine I were using were configured to use Google's DNS at 8.8.8.8 (anycast to the nearest Google DNS, of course), and if the machine were connecting to a router configured to use an ISP DNS like Comcast, like 68.87.73.246, and if that router were connected to the Internet, if I typed 'http://www.example.com' into a browser on the machine, which DNS would my request for that page go through? 20.137.2.50 (talk) 18:40, 14 January 2014 (UTC)


 * Most computer operating systems will attempt to perform name-resolution using the host's configuration. If it fails, they will cascade, recursively, until a name resolution works.
 * For example, hosts (file) explains how this works in general; we also have articles on resolvconf, which is found on many common Unix-like operating systems. It is, ultimately, up to your operating system's implementation choice to decide whether a recursion should proceed up the host's DNS tree or to search the DNS tree provided by the DHCP server.  Most systems will exclusively use the host's configuration (if the host overrides the DHCP settings); and fail on error without consulting the DHCP-provided DNS server.  Nimur (talk) 20:04, 14 January 2014 (UTC)


 * It will use that DNS in Windows. I've used an alternate DNS server before with Charter (or mybe even Comcast, I don't remember for sure) because they would redirect failed lookups to a website they ran with spammy search results and ads. If you clicked the link to disable it it would just serve up a copy-and-pasted IE error page instead. I only changed the configuration on my PC at first until we got around to reconfiguring our DHCP server. I think I had XP at the time, but I doubt Microsoft would have changed the behavior. You can test by running "nslookup example.com" in a command prompt - it will tell you what server it is using. K ati e R  (talk) 12:58, 15 January 2014 (UTC)