Wikipedia:Reference desk/Archives/Computing/2015 June 10

= June 10 =

How to use signature longer than 255 characters?
I would like to use signature similar to this one (Andreyyshore's), so I made it looking like this:
 * &emsp; — &ensp; Obsuser   ✉      &emsp;(example of my signature, don't know how to get date inside )
 * —    A ndreyyshore    T    C    00:26, 30 May 2015 (UTC)   &emsp;(Andreyyshore's signature)

The problem is it's over 500 characters, and can't fit into the box on Preferences page. How to make signature like Andreyyshore's one, with date formatting included? I guess there are many other, more complicated signatures that are surely over 255 character, so there's a way... Thank you in advance! PS I need help on how to include date in the signature in order to be formatted. If I leave span tags opened, all text after the signature will get formatted, so I don't know the way. --Obsuser (talk) 22:58, 9 June 2015 (UTC)


 * Don't do it - it's in contravention of WP:SIG (specifically WP:SIGLEN "Extremely long signatures with a lot of HTML/wiki markup make page editing and discussion more difficult..." and "The software will automatically truncate both plain and raw signatures to 255 characters of code in the signature box."). The signatures you've shown above take up so many lines of markup that it's hard to find your question in amongst it all.  This is unacceptable behavior.  SteveBaker (talk) 03:14, 10 June 2015 (UTC)


 * How did user Andreyyshore have his signature longer than 255? Why is this "unacceptable behavior"? I have read WP:SIGLEN, and thought it was just formally written, because a lot of users use very complicated signatures. How? Here is an example I came across:
 * -- A n T o n i  ( ra zg ov or  )&emsp;(436 characters, User's talk page)
 * How did they even manage to put their signatures' codes into preferences page? --Obsuser (talk) 09:12, 10 June 2015 (UTC)


 * User:Andreyyshore is presumably substituting his signature from User:Andreyyshore/sgn as described at WP:SIG. —Noiratsi (talk) 09:54, 10 June 2015 (UTC)


 * Worth noting the last point of the mentioned rules:
 * Substitution must not be used to circumvent the normal restrictions on signature content, including the use of images, obnoxious markup, or excessive length .
 * CiaPan (talk) 11:36, 10 June 2015 (UTC)


 * It's also worth noting that there are two kinds of people on Wikipedia:
 * Those who think that fancy, customized signatures are unutterably cool and that there are few better uses of time than tinkering with them.
 * Those who think that fancy, customized signatures are a complete waste of time and that what's really cool is to spend time improving the encyclopedia instead.
 * Now, I'm not trying to rain on anybody's parade if they want some personalization and pride of ownership, but please, don't let the over-the-top signatures that are already out there goad you in to some kind of keeping-up-with-the-Joneses race to compete in. —Steve Summit (talk) 13:30, 10 June 2015 (UTC)
 * Its a waste of time coding one now anyway, as the new talk page software (Flow) doesn't support custom signatures. - X201 (talk) 15:30, 10 June 2015 (UTC)
 * If you're seeking a way to waste time, how about writing a MediaWiki-syntax-compliant signature statement that outputs its own wiki syntax program code?  At least this will impress us!  Extra points will be awarded if you accomplish this within a 255 character limit.  Nimur (talk) 15:44, 10 June 2015 (UTC)
 * I'm sensing that I've offended you in some way. I'm not sure how, no offence was meant. - X201 (talk) 19:02, 10 June 2015 (UTC)
 * Not in the least! I'd actually be profoundly impressed if somebody built a recursion-machine out of MediaWiki templates and then used it to quine out the source-code to that machine.  I'd probably start getting annoyed if they used it as their signature.  Nimur (talk) 22:17, 10 June 2015 (UTC)
 * One way to be more compact is to use 3 digit colours insted of 6, eg use #000 for black. Substing could get you a type date. But then you can't easily get a sig with no date. Graeme Bartlett (talk) 22:27, 13 June 2015 (UTC)

Can we say that "Flushing the cache" is "Renewing or Re indexing" the cache?
Thanks, Blessings, Ben-Yeudith (talk) 05:49, 10 June 2015 (UTC)


 * No, flushing just means "emptying". Subsequent use will refill the cache with new stuff, but flushing alone is the act of purging it. -- Finlay McWalterᚠTalk 10:21, 10 June 2015 (UTC)
 * "Renewing" the cache is not terminology I have found in any textbook or manual. But if a fellow engineer told me the cache was "renewed" during normal conversation, I would interpret that to mean the opposite of flushing: "renewing" sounds like you want the stuff in the cache to stay put.  For example, one of the computers I program has a special cache with a time to live (TTL) value: if I perform an operation to use cached data, the TTL is reset (we could say its timeout got "renewed") and I can rest assured that the cache controller driver will not touch my stuff - it won't get ejected, flushed, replaced, for (e.g.) the next 1000 milliseconds.  We have extensive explanations in the CPU cache article (section on policies) and in the cache algorithms article.  Avoid confusion: use standard terminology only!  Nimur (talk) 14:57, 10 June 2015 (UTC)

How VGA monitors to recognize that they have an input signal?
Hello, I want to know how VGA monitors recognize that they have an input signal? What wires in the VGA chord tell the monitor that there is a signal. I found the pin out for a VGA connector here VGA connector. And does any know what the standard wire colors are for each pin of a VGA connector(the pin out doesn't say). Thanks in advance. —SGA314 (talk) 13:20, 10 June 2015 (UTC)
 * The VGA standard does not specify any mechanism for presence detect; but many hardware systems will use the timing signals (VSYNC, for example) or the power (PWR/KEY) and will work when hot-plugged. Nimur (talk) 15:05, 10 June 2015 (UTC)
 * What do you mean "hot-pluged?" —SGA314 (talk) 15:34, 10 June 2015 (UTC)
 * Hot plugging means connecting the cable after both the computer and the display are already powered on, and expecting that this should "work." In the early days of VGA-capable computers, the expectation was that the VGA display was attached (plugged in) before the computer powered on.  Today, VGA (and nearly every other pluggable interface) just starts working as soon as you connect the cord... but that behavior requires that the machines are designed to support it!  Usually, this requires some form of "presence detect" circuitry (to inform one or both machines that the cable has been attached), and some type of suitable "reset" circuitry that will configure the hardware correctly when a new device is attached.  In the case of VGA, the "reset" logic is so simple that it occurs right before the display of every frame anyway!  So, this is one reason why VGA "hot plugging" is so common.  Some computers will also reconfigure hardware or software settings when they detect the display is attached, but this is not actually a standardized mechanism, so it is up to each vendor to determine some method for "presence detection" outside of the standard.  Nimur (talk) 15:41, 10 June 2015 (UTC)
 * Ah ok. I understand now. So you said that some manufactures use the PWR/KEY to detect a signal. How much current typically runs through that pin? The pinout says the voltage is 5 volts but it dosen't say anything about the current. My point in all of this is I want to fool the monitor into thinking it has a signal. Then I want to apply an audio signal to one of the RGB cables to see if various frequencies will produce weird displays on the monitor. And also, I am using a newer flat panel monitor as my display. —SGA314 (talk) 15:50, 10 June 2015 (UTC)
 * Hopefully very little current flows through this pin, but you should be careful! If you do not have specifications and schematics, you can very easily cause permanent damage to your computer or to your display: one hopes that there is an overcurrent protection circuit, but you don't really know unless you have the "blueprints" for everything!  (Hint: your computer vendor won't give you such circuit schematics, because they don't want to encourage this type of hardware hackery that can so easily cause permanent damage).
 * You might be able to get weird displays by splicing wires and shoving analog signals into the wire, but it is safer to experiment using software only. If you really wish to play at the hardware level, I recommend that you buy a cheap computer a like a Raspberry Pi or an Altera DE2 programmable FPGA development board (with VGA capability!)  This way, if you fry some circuits, you're only losing a few dollars, as opposed to your entire primary workstation.  Small computers with simple operating systems are much easier to experiment on: you can easily get access to the hardware frame buffer to directly draw on the monitor (instead of nicely asking some operating system software to do it for you).  In the case of the DE2/Cyclone II board, you can even modify the FPGA firmware to directly control hardware signals that go out the VGA 15-pin connector - you can treat those pins as general purpose I/O!  Nimur (talk) 16:00, 10 June 2015 (UTC)
 * I have a power supply that gives 5V at 1A but I can lower that down to the miliAmp level with some resistors in series. I am not experimenting with my primary work station, I am actually only experimenting with my spare monitor(I don't have any computer hooked up to it) and I am using my rack mount equalizer to generate the various frequencies(I am doing this by hooking the left input to the left output to create feedback then I send that to the right input for small amplification) that will be sent to the monitor. And as for the software aspect, I don't have any access to this type of software. I guess what I can do is I can pull out my multimeter and hook the chord up to my PC and see what current comes from the graphics card. Oh and I already plan on getting a Raspberry Pi 2 soon. —SGA314 (talk) 16:16, 10 June 2015 (UTC)
 * So, if I were to use the PWR/KEY(of which I assume is the white wire) pin to detect signal, where would I connect the negative DC power(black) to? Would it be pin 5(Ground (HSync)) or pin 10(Ground (VSync, DDC))? —SGA314 (talk) 16:46, 10 June 2015 (UTC)
 * you need to provide the monitor with appropriate vertical and horizontal sync signals in order for it to stay awake (i.e., not go into stand-by mode) and display anything. it's not enough to trick it into thinking it's turned on if there's no sync. google vga timing, vga signal generation, vga electrical specification, etc. You can let your graphic card generate the sync, but you have no control over what gets displayed - unless your circuit locks onto the sync, but if you go to these lengths then you could just as well generate it locally. If you simply want the monitor to stay awake while you feed it random singal, splice the RGB lines out of the cable, as Nimur suggested (by literally severing the cable or by making a 1:1 breakout adapter like this (without the leds.)) Asmrulz (talk) 19:52, 10 June 2015 (UTC)

How do you tell if binaries downloaded from SourceForge come bundled with extra software?
If you download a binary file from SourceForge, how do you tell if it is just the app you wanted or if comes with "extras" added by SourceForge? --134.242.92.2 (talk) 19:30, 10 June 2015 (UTC)
 * The green download button says "Installer Enabled" below the word "Download". Underneath the button is a "Direct Download" link to the crapware-free version. Here's an example (FileZilla). -- BenRG (talk) 20:14, 10 June 2015 (UTC)