Wikipedia:Reference desk/Computing

Welcome to the computing section
of the Wikipedia reference desk.

skip to bottom

Select a section:

• Computing
• Entertainment
• Humanities
• Language
• Mathematics
• Science
• Miscellaneous
• Archives

Want a faster answer?

Main page: Help searching Wikipedia

   

How can I get my question answered?

• Select the section of the desk that best fits the general topic of your question (see the navigation column to the right).
• Post your question to only one section, providing a short header that gives the topic of your question.
• Type '~~~~' (that is, four tilde characters) at the end – this signs and dates your contribution so we know who wrote what and when.
• Don't post personal contact information – it will be removed. Any answers will be provided here.
• Please be as specific as possible, and include all relevant context – the usefulness of answers may depend on the context.
• Note:
  • We don't answer (and may remove) questions that require medical diagnosis or legal advice.
  • We don't answer requests for opinions, predictions or debate.
  • We don't do your homework for you, though we'll help you past the stuck point.
  • We don't conduct original research or provide a free source of ideas, but we'll help you find information you need.

Ready? Ask a new question!

How do I answer a question?

Main page: Wikipedia:Reference desk/Guidelines

• The best answers address the question directly, and back up facts with wikilinks and links to sources. Do not edit others' comments and do not give any medical or legal advice.

See also:

• Teahouse
• Help desk
• Village pump
• Help manual

April 24

Recommendation for software to make compilation music CDs

I'm asking for a recommendation for software to make compilation music CDs from other CDs. I want to read in several CDs, store the files on the HD, and then pick sets of them to burn to a CD. Years ago I used Roxio and Nero for this, but they got too difficult to use for this purpose. Bubba73 ^{You talkin' to me?} 00:59, 24 April 2017 (UTC)

For ripping CDs I use Sound Juicer, Ubuntu's default ripper. To compile compilations I use SoX to take the sources and emit a .CDR file which I burn with wodim. -- Finlay McWalter··–·Talk 08:49, 24 April 2017 (UTC)

Just saw this query and thanks for the suggestions. I've used Windows software for the purpose till now but I am inclining towards moving to Linux as I just have had so many problems with databases, and things just stop working with new releases of windows. I think it would allow me more control as I could fix the software if things go wrong. I need interoperability with a spreadsheet and to be able to print labels and CD covers easily. Actually I only put the track names only on the case rather than the CD - this makes for less work. I just print an identifying picture and id on the CDs. Dmcq (talk) 12:04, 24 April 2017 (UTC)

Personally I don't create a cover slip (the audio CDs I create are small samples for a pub quiz, so obviously a track listing is a bad thing). Perhaps unfortunately, I'm a "I'll write a Python program" type person, so if I did need some kind of database and cover-sheet printing solution, that's what I'd probably do, and it wouldn't be helpful for other people in general. -- Finlay McWalter··–·Talk 12:10, 24 April 2017 (UTC)

Thanks, but I should state that I want to use Windows and I don't want to use a command-line interface. Bubba73 ^{You talkin' to me?} 14:19, 24 April 2017 (UTC)

I use a completely customized setup, with a front-end I wrote, a batch files modified from one I found on SO, VLC Media Player and a custom MySQL database for similar functionality at my home. If you're looking to create such a system, I wouldn't mind sharing some of the insights I got from (and difficulties I had) setting that up, but I don't want to bore you to tears if the answer you're looking for is more "SoftwareSoft's Generic Media Player Classic Plus Lite 2017 v1.2 Enhanced Edition does everything you want." ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 14:43, 24 April 2017 (UTC)

Yes, basically what I want is a simple system, really for two slightly different things. (10 I want to read in several CDs and it shows me the complete list of songs. I want to choose songs from that list to burn to a CD. It keeps track of the total amount selected from a CD, so I know how many I can get. After I burn that CD, it marks those songs as done and I can choose another set to burn to another CD, etc. Mode (2) - similar, but I want to read only certain songs from the source CDs. Bubba73 ^{You talkin' to me?} 17:07, 24 April 2017 (UTC)

Windows Media Player should actually do all that. it will rip and burn music, and .wma's have a lossless codec option, so no mp3 distortion. It's just a matter of setting up your library to show all files instead of automatically sorting them. Since you need to be there to swap CDs, I don't see how ripping them one at a time is a bad thing (if you have multiple drives, I believe WMP will rip from all of them simultaneously, though I'm not sure). ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 17:36, 24 April 2017 (UTC)

My first thought was iTunes, which I'm sure will do all that. --Viennese Waltz 07:36, 25 April 2017 (UTC)

I've never used iTunes, but I read that it's really strict with DRM (to the point of adding DRM to ripped music), so I wonder if it's suitable for something like this. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 12:58, 25 April 2017 (UTC)

I don't think it is as strict as it used to be. My brother lost a lot of music he personally ripped when iTunes decided it was pirated and deleted it from his laptop and phone. That was years ago and they've apparently been much better since. 209.149.113.5 (talk) 13:33, 25 April 2017 (UTC)

Same thing happened to a friend of mine, hence my reservations. I'm sure they've gotten a bit better, though. They couldn't possibly have gotten any worse. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 14:07, 25 April 2017 (UTC)

I suspect you have other bugs - Windows or iTunes on Windows bugs. I've used iTunes on the Mac since Powerbook G4 times, and while iTunes Store music used to come with DRM, I've never had iTunes delete any of my music or add anything to ripped music, wether ripped to MP3 or AAC. iTunes has quirks, and they keep deproving the UI, but it is reasonably to use, and it can burn playlist in most formats to plain old CDs. --Stephan Schulz (talk) 17:31, 25 April 2017 (UTC)

My friend (to whom this happened) has a Mac. Used it with his iPod at the time, and now with his iPhone. He also has a (neck) beard and wears flannel to his job in a call center. Sometimes I wonder if I want to remain friends with him. (Yes, I'm being facetious.) He's not particularly technical, though he is young enough to have grown up around computers. It could have been a head space and timing fault. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 17:51, 25 April 2017 (UTC)

Or a classical PBCK error with a touch of Chinese Whispers ;-). --Stephan Schulz (talk) 18:31, 25 April 2017 (UTC)

Well it definitely wasn't Chinese whispers, but it certainly could have been one of the others. He is, after all, marginally smarter than your average box of rocks. Yes, Scott. I know you're reading thing. Knowing my handle on WP and how to find my contributions page does not make you a hacker. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 18:49, 25 April 2017 (UTC)

I tried Windows Media Player. It does rip and burn, bu I still have to do most of the work in making compilation CDs. There is a fluke where it says to drag songs to the playlist, but that doesn't work - you have to right click and send it. But it still leaves most of the work to me - things programs are good at. As far as I can tell, it doesn't tell me the total length of the selected songs until I get them into the area ready to burn. This is needed to see if I can get more songs on the CD or if I have selected too many to go on the CD. Also, after I have used a song on a CD, it doesn't mark that it has already been used. Bubba73 ^{You talkin' to me?} 01:27, 26 April 2017 (UTC)

MySQL, SharpDevelop and the right google search time, then! Seriously, I'm out of ideas that don't involve hacking something together. Sorry bout that. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 04:48, 26 April 2017 (UTC)

Yeah I used to use Windows Media Player. But then its database got into a mess. And so now I hate it though to a much lesser degree that Windows Word which I just hate hate hate. So I moved away to Wiamp, which isn't supported. Dmcq (talk) 12:04, 26 April 2017 (UTC)

April 25

Copying a Bash script from Windows into WSL (CMD) adds carriage returns

I copy a Bash script from a .sh file stored in Windows10 into nano in WSL (CMD). Yet, the script is copied with carriage returns and these break script execution in WSL. Before copying, I access the script file with Notepad++.

The more the CMD window (tty) is narrower, the more carriage returns are created when the script is created.

I start nano with the following syntax (.sh give Bash highlighting) and the CR characters are seen as little Green boxes:

nano ~/ses.sh && chmod +x ~/ses.sh && sh ~/ses.sh && rm ~/ses.sh

Any ideas? Ben-Yeudith (talk) 12:30, 25 April 2017 (UTC)

Windows always prefers 0D 0Ah for a new line in text files. Use Notepad++. NPP also allows to replace the \r\n by \n when setting the checkboxes in the find and replace dialog box, using CTRL+H. && is a new command in the same line, accepted by Linux and Windows. --Hans Haase (有问题吗) 12:41, 25 April 2017 (UTC)

Too bad I didn't mention that (edited to mention): I copy the script TO Nano FROM Notepad++, yet Carriage returns are still created as per the length of the CMD TTY window. This seems unrelated to the particular text editor I copy from, user:Hans Haase. Ben-Yeudith (talk) 12:55, 25 April 2017 (UTC)

Once using a Windows editor, the CRs are inserted. Remove them manually by STRG+H and replace \r\n by \n, using the checkboxes insode the replace dialog box. How did You transfer the file from Linux to Windows? --Hans Haase (有问题吗) 13:06, 25 April 2017 (UTC)

I have no problem to remove them in Notepad++, the problem is that they are inserted when the script conent is pasted in nano (to be later saved in a file and executed inside WSL), hence, they are included inside the nano script. When I do search and replace in nano on either \r\n or \r I find nothing but that doesn't really matter because I am looking for a way to prevent Windows to add these in the pasting anyway. Ben-Yeudith (talk) 13:15, 25 April 2017 (UTC)

The transfer is with WSL. You can copy and paste anything you want in the WSL window and there shouldn't be any problem with that naturally, the point is working cross platform easily with WSL. Ben-Yeudith (talk) 13:17, 25 April 2017 (UTC)

Adjust the checkboxes inside the find and replace dialog! --Hans Haase (有问题吗) 14:42, 25 April 2017 (UTC)

Again, my problem is not with Notepad++. This has nothing to do to any GUI editor in Windows. Ben-Yeudith (talk) 16:59, 25 April 2017 (UTC)

when you say copy, do you mean you copy and paste text from the Windows clipboard into nano which is running in a console window? if you do cat > file.txt (paste, then Ctrl-D) do you still get extra line breaks? Asmrulz (talk) 10:36, 26 April 2017 (UTC)

HI sSer:Asmrulz: Yes, that's what I mean, and the last timre I tried that in the method of (cat > script.sh AND_THEN paste AND_THEN CTRL+D it did work without problems). Ben-Yeudith (talk) 11:12, 27 April 2017 (UTC)

Then I guess it's nano. Asmrulz (talk) 11:45, 27 April 2017 (UTC)

From (very cursory) googling nano seems to be inserting hard line breaks by default [1][2] Normally, editors should just break lines for display (so you don't have to scroll horizontally) but not insert linebreaks into the file when saving. Try to alias nano to nano -w. Is it some remote thing where the editor is running on a remote machine and the TTY is on yours? If so, find a way to copy files to the remote machine without having to paste text into an editor, such as with scp, netcat or something Asmrulz (talk) 11:57, 27 April 2017 (UTC)

Sadly, User:Asmrulz, it happens when I paste the same code in heredocuments as well, not only with regular scripts in Nano... If I use cat > script.sh AND_THEN paste AND_THEN CTRL+D, it works with heredocuments as well, but if I don't, they too fail. — Preceding unsigned comment added by 79.178.144.67 (talk) 13:02, 27 April 2017 (UTC)

I'm not sure how to fix it in nano, but I do have some notes on how to fix this using vi:

To remove the ^M characters at the end of all lines in vi, use:

 :%s/^V^M//g

The ^V is a CONTROL-V character and ^M is a CONTROL-M. When you type this, it will look like this:

 :%s/^M//g

Hope this helps. Random character sequence (talk) 17:19, 27 April 2017 (UTC)

For solution see here. — Preceding unsigned comment added by Ben-Yeudith (talk • contribs) 16:41, 28 April 2017 (UTC)

April 26

Smart phone specification

What is the processor speed and RAM required for a phone that could last for 5 years...? 116.58.204.152 (talk) 19:40, 26 April 2017 (UTC)

That's impossible to say, as we really can't predict what the operating systems and apps will require 5 years from now. StuRat (talk) 20:30, 26 April 2017 (UTC)

Which isn't to say that we don't try. Honestly, the best answer I can give to this question is "A phone that won't be released for at least two more years." ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 20:45, 26 April 2017 (UTC)

All we can do is look into the past.

A reasonable number of people, allegedly including Donald Trump[1], still use the once-popular Samsung Galaxy S3.

If Donald Trump bought the phone the day it came out, then that phone will be five years old in 32 days. Presumably he's still happy with it.

The President aside, I used to carry an S3, and I now keep it turned off in a drawer as a backup in case I lose my current phone and can't afford to replace it. It's a nice little phone and it wouldn't kill me to use it again.

I think that's the best answer we can give you. Five years ago, if you had bought a newly released, top-of-the-line phone with a replaceable battery, you'd still have a perfectly fine phone today.

You'll have to use your judgement as to whether that wisdom will hold true for the next five years. ApLundell (talk) 00:58, 28 April 2017 (UTC)

We should also point out that if you're OK with using 5 year old phones, you can save a lot of money by buying them when they are already several years old, even if you end up buying one every couple years instead of every 5 years. This is due to bleeding edge technology pricing. StuRat (talk) 19:28, 28 April 2017 (UTC)

RAM has still increased the wait states or CL when increasing the frequency. This means it is waiting more cycles of an higher frequency. Is my car in Europe faster than in the US? In the US it drive it 65 MPH, in Europe 107 km/h. Whats the different? Yes it is the same speed. But using two memory channels make it transfer the double data rate within the same technology of RAM. --Hans Haase (有问题吗) 23:56, 28 April 2017 (UTC)

.apk file

Looking for ‘’.apk’’ file type(s) opensouce software(s) similar to, or exactly like, or the "MS Office" itself, without on-line connectivity issue.

1) Word, Excel and Outlook are very important; require the full functionality… 2) I would like to sync the Outlook with the PC Outlook without the connectivity issue, desirable. 116.58.201.134 (talk) 20:03, 26 April 2017 (UTC)

There's always AndrOpen Office. It requires Android 2.3 or later. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 20:47, 26 April 2017 (UTC)

AndrOpen Office is pretty sketchy. It is a fork of Apache Open Office, but ... it doesn't seem to be open source. Which is obviously not right or proper. And it is ad supported!

There's [LibreOffice] (.apk available), which is pretty incomplete.

I'm not sure there is a good open-source office suite for android. Most people use Google Docs which, of course, requires access to the Google cloud, and I don't think it's open-source in any meaningful way. ApLundell (talk) 14:36, 27 April 2017 (UTC)

April 27

Monitor cracking sound

My monitor (ROG Swift '27) sometimes, but very rarely, make a relatively loud cracking sound. Like cracking your knuckles, whether it's on or when it's been off for a while (even hours). I've read that it's apparently the plastic shell that's expanding and contracting due to temperature?

I believe that's relatively normal and not harmful, at least according to Google? I believe my PlayStation did the same when I owned one. My PC does the same. Matt714 (talk) 09:24, 27 April 2017 (UTC)

• By your description, it could be the same phenomenon as in a pop pop boat, but it is hard to know for sure if you have not identified where the noise comes from. Tigraan^{Click here to contact me} 11:45, 27 April 2017 (UTC)

• It's relatively normal for plastic components to make cracking/popping noises as they expand and contract. Plastic expands and contracts quite a bit as it heats/cools. (Expansion of fitted parts, if they don't slide smoothly, puts them under stress. I believe the actual noise occurs when two pieces under stress suddenly slip.) Sometimes improperly installed plastic plumbing will have the same problem when you run hot water through it.

Some Apple Mac desktop machines are notorious for this.

I can't find a good article explaining this, but here's a FAQ on Samsung's website about one of their TVs. [2]

ApLundell (talk) 14:16, 27 April 2017 (UTC)

As for how to fix the problem, if the plastic case is attached with multiple screws, perhaps loosening or even removing a few might give it room to expand and contract. If this is not done, the stresses may ultimately cause the case to crack and split. StuRat (talk) 15:08, 27 April 2017 (UTC)

Cracking sound usually comes from sparks of high voltage. Since LED back lights is should be obsolete. CCFL back lights still use about 3 kv inverters. LED inverters use higher voltages as wells due the LEDs are in series circuit. ASUS specified the ROG Swift '27 with an in panel back light inverter. If nobody took the monitor wet, it might be the power supply caught dirt of some capacitors begin failing. --Hans Haase (有问题吗) 23:47, 28 April 2017 (UTC)

The Samsung thing was reassuring. I've asked elsewhere and many reported the same thing, but no failure even after years. The constantly vacillating temperature in Québec right now probably does not help. My PC does it as well. Matt714 (talk) 00:37, 29 April 2017 (UTC)

Non-support of font tags

As I understand it, <font>...</font> tags were deprecated in HTML 4.0 (in the late 1990s, according to HTML), which is why their continued use in customized Wikipedia signatures is controversial. I'm on one side of the fence or the other, depending on the answer to one question: What is likely to happen with all the font tags in our archives if (when) browsers finally drop support? Will browsers continue to recognize them but ignore them, or will they be exposed on the rendered page? Are there any precedents to judge by? ―Mandruss ☎ 16:08, 27 April 2017 (UTC)

Currently, every web browser that I use ignores unsupported tags. So, if a tag is not supported, it doesn't show up to the user. It is simply ignored completely. I see no reason to assume that it will change if a browser stops parsing a font tag. It will just see the tag and ignore it. No harm. Remember that failing gracefully is important in HTML. 209.149.113.5 (talk) 16:20, 27 April 2017 (UTC)

So a current signature
Example^talk 14:24, 22 April 2017 (UTC)
will display as:
Example^talk 14:24, 22 April 2017 (UTC)
not as (font changed to fint):
<fint face="Times New Roman" color="#930">Example</fint>^{<fint color="#D7000B">talk</fint>} 14:24, 22 April 2017 (UTC)
and we would expect that to hold true until the end of time, or the end of Wikipedia as we know it, whichever comes first? ―Mandruss ☎ 16:37, 27 April 2017 (UTC)

While that's true, there's also the issue of mediawiki parsing. For example <foo>bar</foo> shows up explicitly without me using <nowiki> tags because mediawiki doesn't recognize it as a valid HTML tag. That being said, I doubt the developers at WMF will ever decide to just drop a recognized tag like that. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 17:00, 27 April 2017 (UTC)

So you're ok with all of your existing sigs in the archives rendering as ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it.. If you're happy I'm happy, it will just be 17 wasted and superfluous characters of wikitext for each of your signatures. ―Mandruss ☎ 17:45, 27 April 2017 (UTC)

Well, my sig doesn't use a font to produce the characters, it uses unicode characters (elder futhark runes, to be specific). But it doesn't bother me too much for it not to render properly from time to time, because most of the time it does. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 17:58, 27 April 2017 (UTC)

You will lose the green in all existing sigs when the support is dropped. ―Mandruss ☎ 18:22, 27 April 2017 (UTC)

Wow, I honestly didn't realize I had used the font tag. Well, I've changed it to a span tag now. But no, it wouldn't bother me that much. I only picked green (and added the shadows) because it makes it easy for me to spot my signature on talk pages, to know where I left off. The only real vanity in my signature is the phrase "tell me all about it" and the runic characters. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 18:49, 27 April 2017 (UTC)

Just out of interest, what should the seven boxes really look like if I had a runic font? Dbfirs 19:46, 27 April 2017 (UTC)

@Dbfirs: Something like this: File:Mandruss-screenshot.png. ―Mandruss ☎ 20:55, 27 April 2017 (UTC)

@Dbfirs: Check out Runic (Unicode block)#Fonts for some free fonts that support it. Arial is one of the fonts that do, and while it's not free, it should be included with most modern web browsers. If you have one of those installed and your browser doesn't display it check out this site for instructions on how to get it working. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 21:13, 27 April 2017 (UTC)

Oh, and while it's acceptable to call them "boxes" under normal circumstances, when they show up in my signature, they're "squares". ;) ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 21:15, 27 April 2017 (UTC)

Needless to say. SpongeBob BoxPants would make no sense whatsoever. ―Mandruss ☎ 21:19, 27 April 2017 (UTC)

Thank you for explaining the "squares". Now that I know what they mean, I won't bother installing elder futhark runes, but just think of you as squarepants (no offence intended). Dbfirs 07:58, 29 April 2017 (UTC)

Curious - why were font tags deprecated??? Whoop whoop pull up ^{Bitching Betty | Averted crashes} 19:13, 27 April 2017 (UTC)

Because CSS handles it better and easier. Notice how the signature in my last comment is slightly larger than this one (and the previous ones?) That's because my use of the font tag broke the css class I'd put it into. I didn't realize it because I got the result I wanted, but once I switched to a span tag, the CSS class started working again. (I removed the class from my signature between then and now). ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 19:27, 27 April 2017 (UTC)

For the same reason, bold, italic, and underline were initially deprecated in HTML4 and then reintroduced in HTML5. I assumed font would be reintroduced as well, but it wasn't. 209.149.113.5 (talk) 11:55, 28 April 2017 (UTC)

Yeah, those are tags that a lot of people use inline. I figure they brought them back because <b></b> is easier to use than <span class="boldDefault"></span> where you have to set up a bold, italic and underline class for each typography used on the page. I know I appreciated it for that reason. I've also noticed that the new implementation works better with complex CSS rules. The older ones (similar to the <font></font> tag) could screw with class properties of tags like <p></p> and <span></span>, though it seemed to handle <div></div> just fine. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 13:24, 28 April 2017 (UTC)

Javascript bitwise operations

How do bitwise operations work in javascript since everything is a float? (note that there is no error when you do something like 5.2 & 3.6). 70.190.164.57 (talk) 20:19, 27 April 2017 (UTC)

The bitwise operators work on signed 32 bit integers. If the operand is a double float (and this is the basic type for a JavaScript Number) then it will be cast to a signed int32 first. As doubles are pretty long (52 bit fraction) then this is a practical process, although there's obviously a minor overhead (but hey, that's going to be the least of your worries in any plausible JavaScript context).

There's also a lot of scope for optimisation here. The JavaScript engine doesn't necessarily convert back to the double float, unless it needs to. So complex bitwise expressions could be processed almost entirely in the int form (but you'd never know). Andy Dingley (talk) 20:55, 27 April 2017 (UTC)

Display Resolution

What is the difference between "1280*720" and "720*1280" on a phone? 43.245.120.134 (talk) 22:53, 27 April 2017 (UTC)

AFAIK resolution is always width x height. So the first would be wider than tall and the second would be taller than wide. Landscape vs portrait orientation. Both measurements are in pixels of course. ―Mandruss ☎ 23:00, 27 April 2017 (UTC)

I'm unsure if that truly the case with the phones; you'll find websites advertising either ways ("1280*720" and "720*1280"). 103.67.158.220 (talk) 14:07, 29 April 2017 (UTC)

April 28

How do I get Gmail to stop using captchas ?

It used to just let me log in with my username and password, and remembered both on my home PC, but now they started adding captchas randomly, without even asking if I wanted them, which I find intensely annoying. How do I turn them off ? StuRat (talk) 04:38, 28 April 2017 (UTC)

I assume you're not doing anything that would cause google to think you're using a brand new computer each time. (Cookie cleaners, incognito mode, overly-aggressive browser privacy plugins, etc.)

It's possible that Google's mysterious hacking detection systems have decided your account is under attack or at risk. Do you have an email app running on a phone or PC that is constantly checking your email with an out of date password? That's a common cause of this.

Allegedly some causes of this problem can be cleared by going to https://accounts.google.com/b/0/DisplayUnlockCaptcha

ApLundell (talk) 14:34, 28 April 2017 (UTC)

Not doing any of that, no. Maybe it's the IP range they don't trust. I'll check out that site, thanks. StuRat (talk) 14:39, 28 April 2017 (UTC)

Uh, I suppose we should at least pay lip service to the idea that it might not be a false alarm, and that Google really might have good reason to keep checking your humanity. If there's a risk that someone really is trying to dictionary-attack your gmail account, switching your account over to two-factor security would be a good idea.

I believe that would stop them from offering captcha checks, but of course two-factor can be just as irritating as captchas. ApLundell (talk) 14:58, 28 April 2017 (UTC)

(edit conflict) It might have decided your IP range was suspicious or something. If you stay on the same address for a while it might settle down. For all sorts of reasons I prefer Fastmail to Gmail, though it isn't free (but there's no ads, it doesn't spy on you, etc). That would be another way to fix it. 173.228.123.121 (talk) 14:35, 28 April 2017 (UTC)

• Regardless of whether you're actively being hacked or not, ApLundell's suggestion is a very good one. Two-factor authentication is really something you should enable whenever possible. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 18:00, 28 April 2017 (UTC)

I should point out that the login panel has changed, so this new security feature may just come with the new login screen. StuRat (talk) 19:30, 28 April 2017 (UTC)

Is somebody brute-force attacking the account? --Hans Haase (有问题吗) 23:37, 28 April 2017 (UTC)

I have no reason to think so. StuRat (talk) 00:47, 29 April 2017 (UTC)

test a page interacting with cam on Chrome

I have to test a page interacting with cam on Chrome. So I'm trying to launch Chrome with option '--user-data-dir=/test/only/profile/dir', yet I get the error 'Chrome cannot read and write to its data directory', although I set custom permissions to AppData Chrome folders.. Could you please help me?

Cheers --12:09, 28 April 2017 (UTC)~~ — Preceding unsigned comment added by Luga lambrusco (talk • contribs)

Cron expressions

What do these two cron expressions mean?

Start time:

0 0/1 * 1/1 * ? *

Stop time:

0 0 2 ? * * *

Thanks, †dismas†|^(talk) 14:37, 28 April 2017 (UTC)

As far as I know, cron expressions have only 5 fields (minute, hour, day of month, month, day of week), so those examples are ill-formed.

According to man 5 crontab on the NETBSD UNIX system I have access to, "?" means "a single value randomly selected when the crontab file is read". For example, if it's in the hour field for an action to be performed daily, that action might be performed at 03:00 every day and then change to 23:00 when the system is rebooted or the crontab file is changed. And / means "every nth". For example, in the hour field */2 means hours 0,2,4,...,22 of the day, or 0-10/2 means 0,2,4,6,8,10. So as far as I can see it makes no sense to write /1 or to use / with a single number on the left.

--76.71.6.254 (talk) 21:37, 28 April 2017 (UTC)

The cron replacement nncron extends the cron syntax to allow a sixth field, to specify the year. [3] I'm not aware of any cron replacement that uses seven fields but there might be one. "?" is not standard cron syntax, but nncron uses it to mean "the time that the daemon started". I'm also unsure what the OP means by "start time" and "stop time". Each cron specification specifies the time that a command is to be started. There's no such concept as a "stop time" in standard cron (what would it do, kill the process if it's still running at that time?) CodeTalker (talk) 21:50, 28 April 2017 (UTC)

iphone 5S with no battery

I can get an iphone 5S cheap that has a bad battery. Rather than replacing the battery I'm thinking of removing it completely, and using an external power pack like a Mophie. Does anyone know if the 5S works ok with no internal battery? Yes I know it's easy to replace, but I don't like the iphone feature that it's impossible to know that it's completely powered off. Unplugging the external battery would fix that. Thanks. (Also: how long does it take to cold boot a 5S from powerup? Same question for Ipod Touch 6th gen I guess). 173.228.123.121 (talk) 14:38, 28 April 2017 (UTC)

This is a pretty bad idea and will absolutely void your warranty. It might "work" - the phone might turn on - but you probably can't even begin to imagine the vast number of ways this will change the device's behavior. It might also turn your phone into a devastating fire-hazard!

Apple's official information page says: "Don’t attempt to replace the iPhone battery yourself—you may damage the battery, which could cause overheating, fire, and injury. The lithium-ion battery in your iPhone should be serviced or recycled by Apple or an authorized service provider...", and points you to the Battery Service webpage.

Do you enjoy unpredictable software and hardware behaviors? Do you enjoy debugging them without access to documentation? Do you think you know enough about lithium batteries to prevent lithium fires? I'm sure you've carefully reviewed the chemical cell safety data sheet, the power controller ASIC documentation, and the software design specification for the battery controller, because you magically got access to all of these documents and could afford the time and engineering-talent to review them? You're very sure that what you're about to do is safe and will not cause over-current or short-circuits or any other electrical or chemical hazard? Because that's a risk that Apple specifically points out when it warns you not to try to replace or modify the battery yourself.

Nimur (talk) 20:09, 28 April 2017 (UTC)

This advice is questionable. Whatever crap Apple may say, unless you screw up when you remove or dispose of the battery and it catches fire, there would have to be something incredibly wrong the iPhone for it to catch fire just because the battery is removed. Software design specification for the battery controller etc are red herring since the OP specifically said they aren't planning to replace the battery. They're simply going to use it without a battery but without an external power plug. The iPhone may not be designed to be used without a battery (as I said below, it most likely simply won't work) but it should be sufficiently designed such that it won't catch fire when someone does try to use it without a battery unless Apple designers are complete idiots. And hopefully you Nimur can attest that they're not. The battery pack the OP is using, if it's a decent one, will have it's own built in safety, such that even if the iPhone does try to do something stupid like draw 10A, it will prevent this and definitely prevent the lithium ion battery inside the battery pack from catching fire. If it doesn't then it's a piece of junk and having access to a wealth of Apple technical document doesn't help. (In other words, protecting the battery in the power pack is largely the responsibility of the power pack designers, not Apple.)

Now removing a non removable lithium ion battery isn't without risks, and yes you could cause a fire if you majorly screw up. Definitely you should have knowledge of the risks involved, and how to deal with them before trying it. But you do not need, and we can be fairly sure not even all Apple certified repairers know all that info about the software controller etc. It's not germane to what they're doing, which is solely to open the iPhone and remove the battery. Even if they have access to the documentation, it's largely a moot point. If you accidentally poke a hole in the battery, you need to know what to do right now, not read up on crap about the software controller. (Of course you should be sufficiently competent that this never happens.) Disposing of the battery safely is another minor concern, hopefully your jurisdiction has some sort of hazardous waste scheme to deal with. But anyway, even if you do something incredibly stupid like throw the battery out with the regular trash, maybe you'll cause a fire in the rubbish truck or dump (in reality probably not), but it's not going to affect your iPhone and battery pack. Well unless the fire spreads to your house or something.

Definitely the people who install the battery in the China in the first place do not know any of that stuff, although it's obviously a lot harder to safely remove a battery than it is to safely install it in the factory. A middle ground would be those who are helping in the recycling of the iPhone. Apple doesn't have the capability (nor I'm thinking the policy even in a number of places where they official sell the iPhone) to be the ones collecting all iPhones for recycling. [4] This means it's down to other ewaste experts to deal with. And we can be fairly sure these people do not have, and it would be ridiculous to expect them to have, all that info before they remove the iPhone battery. They just need the technical expertise on how to safely remove the battery (including what to do if something goes wrong), and what to do with it after.

Nil Einne (talk) 02:15, 29 April 2017 (UTC)

USB chargers just limit the output voltage an the output current. This are not power supplies, they are still chargers. If a computer or similar logic device needs more power in a peak, the voltage drops and causes a brownout of the CPUs. A battery filters the peak. If there's no battery, the device still might not startup. Wen playing with old mobile phones for scrap, carefully have an experienced person remove the battery, even when lithium batteries are blown up of got thick, be careful, it is already damaged! Opening or hurting the lithium battery might cause immediate fire and explosion.[5] --Hans Haase (有问题吗) 23:35, 28 April 2017 (UTC)

It's unlikely this will work. Pretty much all Android phones I've ever owned with removable batteries do not work without the battery. There is no reason an iPhone which does not even have a removable battery is likely to be any different. And it's not impossible the peak power draw of the phone is actually higher than that supplied by the charger even if it's a 2.4A one. Unlike some of many laptops, phones simply aren't generally designed to be used without the battery. Nil Einne (talk) 01:40, 29 April 2017 (UTC)

Thanks all. Nil's info seems particularly relevant, that Android phones don't work without batteries. I'd never tried it with any kind of phone so didn't know. So yeah, I'd expect the iphone to be the same way and therefore my scheme is unlikely to work and I guess I won't pursue it. Absent that approach, if I have to get an iphone at all, it will probably be an SE.

Regarding replacing the iphone 5s battery: 1) I'm not worried about the warranty since the phone is presumably out of warranty; 2) I didn't want to replace the battery, but rather, to remove it completely and operate the phone on external power without it; 3) I'm not too worried about replacing the battery either, it's not brain surgery. Yeah there's that Apple info page, but there was also a tag on my mattress that said "do not remove this tag under penalty of law". I cut it off while no one was looking and the police never came after me, so now I take those sorts of warnings with a grain of salt. 173.228.123.121 (talk) 03:37, 29 April 2017 (UTC)

It might help to replace the battery with a large capacitor. --Hans Haase (有问题吗) 12:31, 29 April 2017 (UTC)

Headphone jack vs USB

The headphone socket on my Toshiba laptop is going. I have to hold the jack in place or I lose some of the audio. Will a headset connected to a USB port give me the equivalent audio quality? I assume buying one of those will be cheaper than getting the socket repaired or replaced. Rojomoke (talk) 22:27, 28 April 2017 (UTC)

Short answer: Yup.

Long answer: You can actually drastically increase your audio quality with an external sound card (and keep your favorite headphones). I recently picked up this one for one of my home computers. I do not recommend getting a gaming headset, as the audio quality is utter crap, even with the expensive ones. However, if you're not on the same level of snobbish audiophile/geekiness that I'm at, you may not notice a difference. ᛗᛁᛟᛚᚾᛁᚱPants Tell me all about it. 22:41, 28 April 2017 (UTC)

Are you sure it's the socket that's going bad and not the jack on the headphone cord? In my experience the latter is more likely to fail, due to a broken/frayed wire or similar failure. You can check by testing with a different set of headphones. If you have expensive headphones and the jack is bad, you can replace it for about US$5. CodeTalker (talk) 22:47, 28 April 2017 (UTC)

Maybe the phone connector (audio) jack needs just to be cleaned or resoldered.[6] Some were assembled in Surface-mount technology in portable devices,[7] but not on desktop mainboards. Some basic knowledge of metallurgy and electronic might be useful. While computer audio jacks close an switch on the back end when a connector is plugged, analog hifi jacks open the line(s) trough and disable the internal microphones(s) or speaker(s). Audio adapters for USB are USB sound cards. Sound cards have an analog and a digital part. For the analog circuit, separate power input pins are on the device. A better filtered operating voltage should be avail for this. Today, the costs of such separate voltage regulators are the differences in cheap and decent sound cards. It still might be possible to achieve something acceptable due USB devices are 5 volts tolerant 3.3 volts devices. Just a low-pass filter for each part of the audio device causes the first huge reduction of noise. An constant voltage delivered from a linear voltage regulator is even better, but not achievable without an boost converter inside an USB device an the boost converter is sill a source of noise. On mainboards the AC'97 an its successor, the Intel High Definition Audio codec devices are still analog/digital converter devices. The bus interface and other logical circuit has been moved into the chipset. --Hans Haase (有问题吗) 23:10, 28 April 2017 (UTC)

I use a Musical Fidelity V90-HPA and it is very flexible - I use it for more than I intended. It is a D/A converter, has a USB input and RCA inputs and outputs. It has a switch to switch between inputs. I have the USB going to the computer, of course. I also have a stereo system next to my desk and I have the RCA inputs and outputs going to it. With this arrangement, I can play either the computer or the stereo through the headphones or play the computer sound through the stereo. And it sounds a lot better than plugging headphones into the computer. Bubba73 ^{You talkin' to me?} 02:41, 29 April 2017 (UTC)

April 29

Box-drawing character

I'm looking that the tables in Box-drawing character to try to get the characters with the alt-codes. If I do alt-2510 I get ╬ when I expect to get ┐. Others give different characters too. What is wrong? Bubba73 ^{You talkin' to me?} 01:30, 29 April 2017 (UTC)

Not sure why the offset, but that's close to the one you want. You might just experiment with numbers nearby until you find the ones you want. StuRat (talk) 03:11, 29 April 2017 (UTC)

Check the character encoding that your viewing software (browser, tty emulator, or whatever) is set to use. 173.228.123.121 (talk) 03:43, 29 April 2017 (UTC)

Different Google accounts on Android phone for email vs contacts and calendar

I have two Android handsets, and two different numbers for them. Can I set up the phones to share the same Google contacts and calendar, but use different Gmail accounts? 94.119.64.29 (talk) 10:35, 29 April 2017 (UTC)

dropbox, syncing and data

Hi, if I update a dropbox file, say by making a small edit, then clicking ctrl-s, when it syncs, does it sync the whole file? So if I have a 1mb file, and I click ctrl-s, will it save the whole 1mb? This might be chewing data up, and I have only got cellular broadband. IBE (talk) 13:40, 29 April 2017 (UTC)

nbn and cabling requirements

Hi, I've asked similar questions before, and gotten good answers, but this is slightly different. Officially, in Australia, your NBN provider (eg. Optus) will install an HFC (cable) connection for you, at no cost. One provider confirmed this was the case, though when I asked them to email this information, they said yes but didn't do it (presumably no one wants that paper trail to lead to them). So before bothering to hope they will do anything useful, I'm turning here, where I always get the best service (thanks!). I live in a block of apartments, and adding a cable outlet would mean fishing the cable through the wall, between my premises and the neighbour's. Does anyone know, is this generally possible? Is it essentially an easy job to thread cables through the gaps between walls in an apartment complex? Is it fairly quick, simple and conventional? Then I will know what generally to expect - eg. if it is a hard thing, I will be suspicious of any company telling me it's free and simple. Thanks, IBE (talk) 13:49, 29 April 2017 (UTC)