Wikipedia:Reference desk/Archives/Computing/2016 May 17

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May 17

Importing CD music into iTunes

I have an iMac running El Capitan with the latest version of iTunes. I'm trying to copy the music on the CD into iTunes (the CD shows up in iTunes). "Copy" doesn't work. How do I import them? — Melab±1 ☎ 00:04, 17 May 2016 (UTC)

Surely a quick google would reveal this has been answered many times before. Vespine (talk) 01:28, 17 May 2016 (UTC)

Raspberry Pi file editing

I'm not exactly a newbie to the Raspberry Pi, but have not been able to make much use of it. The problem is that permission to save changes is denied after a file has been edited, so the effect is that I cannot edit files. I'm also not permitted to change file permissions. Setting myself as Superuser (sudo su) doesn't help. What next? Akld guy (talk) 03:43, 17 May 2016 (UTC) The file that I particularly want to edit is in a folder in the /etc directory, if that helps diagnosis. Akld guy (talk) 03:52, 17 May 2016 (UTC)

After following this_advice (which I have followed many times before), the settings are now -rwx for the file I want to edit, so the 'w' allows me to write and I'm no longer denied permission to save after editing. Targeting the file itself seems to have done the trick. That is, instead of doing:

$ chmod +w ./ax25 <-- to set write permission on every file in folder ax25, or

$ chmod +w ./ax25/axports <-- to set write permission on file axports

I went into the subfolder ax25 and targeted the file directly, viz:

$ chmod +w axports <-- successful

However, the problem now is that after editing and clicking Save, a box pops up saying "Can't open file to write", with the only option being to click OK and abandon the edit. I'm stumped. Akld guy (talk) 05:56, 17 May 2016 (UTC)

Couple quick answers:

• There's probably nothing specific to the RPi here -- this is all straightforward Unix/Linux stuff.
• Which version of Linux did you install on your pi? Raspbian? Something else?
• You've got some misconceptions, some probaby spawned by that web page you linked to (which isn't perfect). In particular, chmod +w ./ax25 does not "set write permission on every file in folder ax25". What it does is set your ability to create and delete files in folder ax25.
• The behavior you're describing is unusual. If you're really having the same problems as root, it's even more unusual. It's likely that there are some key differences between what you described, and what actually happened.

Couple suggestions:

1. Do a chmod 775 /etc/ax25 to make sure the permissions on that folder are sane. (It's likely they got into a really weird state while you were flailing around.)
2. Do a cd /etc/ax25. Now you're "in" that folder, so you can manipulate its files more easily. (Not being "in" the folder shouldn't have prevented you from doing anything, but it's way more convenient not to have to type "./ax25" all the time.)
3. Very carefully type these commands:

ls -ld /
ls -ld /etc
ls -ld /etc/ax25
ls -l /etc/ax25

Now, again very carefully, copy and paste the results here so we can see what's really going on.

—Steve Summit (talk) 12:48, 17 May 2016 (UTC)

Version is Debian. Yes, that web page is not exactly ambiguous but doesn't tell the entire story. OK, I did the chmod 775 /etc/ax25 with no problem, then the cd /etc/ax25 and got the report: cd: command not found.

So I went into the folder step by step like this cd /, cd etc, cd ax25.

ls -ld / resulted in drwxr-xr-x 21 root root 4096 Jan 1 1970 /

ls -ld /etc resulted in drwxr-xr-x 112 root root 4096 May 17 13:50 /etc

ls -ld /etc/ax25 resulted in drwxrwsr-x 2 root root 4096 May 17 18:03 /etc/ax25

ls -l /etc/ax25 resulted in:

total 24

lrwxrwxrwx 1 root root 20 May 17 12:32 ax25 -> /usr/local/etc/ax25/

-rwxrwxrwx 1 root root 178 May 18 00:45 ax25d.conf

-rwxrwsrwx 1 root root 1508 Apr 4 2015 ax25-up

-rwxrwsrwx 1 root root 200 Sep 10 2014 axports

-rwxrwxrwx 1 root root 73 May 18 00:30 axports.1

-rwxr-sr-x 1 root root 139 Sep 10 2014 nrports

-rwxr-sr-x 1 root root 111 Sep 10 2014 rsports

Akld guy (talk) 14:52, 17 May 2016 (UTC)

In other words I managed two or three hours ago to get the write permissions correct and am now able to edit and save the axports and axports.1 files. So the original complaint is gone. I got the permissions correct by doing sudo chmod +rwx axports, sudo chmod g+rwx axports, and sudo chmod o+rwx axports. I did the same for axports.1. In other words I had to set all three, and it was successful. I now would like to know how axports and axports.1 differ. As I understand it, axports.1 is the readable file, with axports as a kind of dummy? Akld guy (talk) 15:03, 17 May 2016 (UTC)

I don't have time for a long answer, but a couple more things:

• You said you tried cd /etc/ax25 and got "cd: command not found". I'm sorry, but that's nearly impossible. Then you said that the sequence cd /, cd etc, cd ax25 worked -- and now what you've told me is completely impossible! It's very hard for the cd command to be missing, and the fact that it worked when you did it in three steps proves that the cd command is present. So -- and again, I'm sorry if it sounds like I'm accusing you -- you either didn't exactly type cd /etc/ax25, or you didn't exactly get the message "cd: command not found". (Possibly both.)
• Those s's scattered around in the file permissions (rwxrwsrwx and rwxr-sr-x) are suspicious. They mean special, magical things that I can't remember and never even really learned. They're probably causing at least some of your problems.
• The file you want to be editing is probably axports. The file axports.1 you have is probably a backup copy that you or someone made.

—Steve Summit (talk) 16:58, 17 May 2016 (UTC)

OK it's morning (7:30) and I've had a few hours' sleep. cd /etc/ax25 and cd /, cd etc, cd ax25 both work, whether I'm Superuser or not. I can only assume I might have already been in / or even /etc/ax25 itself when I tried the former method. The latter method does indeed work, and it might pay to remember that the Raspberry Pi may do things differently in its Debian version than other Linux versions.

Yes, the s's are probably causing the current problem, which is that trying service ax25 start gives error message Unit ax25.service failed to load: No such file or directory. Akld guy (talk) 19:37, 17 May 2016 (UTC)

Glad to hear things are starting to work. More points:

• It doesn't matter where you are when you type cd /etc/ax25; the leading / makes it an absolute (as opposed to a relative) path.
• When I said the s's are probably causing problems, I meant the weird ways that permissions were changing all by themselves, and the files weren't writeable even when it seemed they should have been.
• The service command runs a script in /etc/init.d. In your case, we can tell that there's a script there called ax25. It's likely that this script tries to start an actual program that performs the ax25 service, and it's likely that the actual program is missing, and is resulting in the "service failed to load: No such file or directory" message. (There's a cardinal rule of Unix error messages -- one that's tragically often broken, and is in fact being broken here -- which is that when a program prints an error message like "No such file or directory", it is always supposed to also print the name of the file or directory it was trying to open. Without that, it's very hard to figure out what the missing file is, and how to repair it.) —Steve Summit (talk) 20:49, 17 May 2016 (UTC)

Just one point. The command

   $ chmod +w ./ax25 

does not "set write permission on every file in folder ax25", as claimed above. It sets write permission only on the directory (folder) ax25 itself. If you want to affect the directory and all the files under it, you need to use the -R (recursive) option. That is:

   $ chmod -R +w ./ax25

At leastm this is true on any UNIX/Linux version I've used for many years, and I assume it applies equally to the Raspberry Pi. --69.159.60.83 (talk) 21:36, 17 May 2016 (UTC)

Thank you. That confirms what User:Steve Summit wrote above. I had misinterpreted what the page I linked to was telling me. Akld guy (talk) 21:51, 17 May 2016 (UTC)

@Scs: I used File Manager to locate /etc/init.d and opened the file ax25 in the Text Editor. The following lines are present:

NAME=Ax25

DAEMON=/usr/local/etc/ax25/ax25-up

PIDFILE=/var/run/ax25.pid

test -x $DAEMON || exit 5 # Exit - Pgm Not Installed.

Another 34 lines (excluding comments) follow and relate to start, stop, restart, and status of the service, but I think they are not relevant and the lines I typed above seem to be the point of failure. The DAEMON path is good to /usr/local/etc/, but ax25 is not present in /etc. Similarly, the PIDFILE path is good to /var/run/, but the ax25.pid is not present. The folder udev, which I know is needed for what I'm setting up, is present in /run.

The ax25/ax25-up are in /etc, ie. /etc/ax25/ax25-up. Since udev is where it is, do I move them into /usr/local/etc and what is the syntax for that? I've been unable to locate ax25.pid. Akld guy (talk) 22:39, 17 May 2016 (UTC)

I don't understand. Why didn't you just use sudo vim yourfilename to edit the file rather than change the permissions. To move a file, do (sudo if necessary) mv origin_filename destination_filename. It may be better to simply make symlinks if you think there is any chance other programs depend on those files living on those places. You can make a symlink with ln -s real_file_path desired_link_path 2001:630:12:2428:B437:CFEC:FB82:E32 (talk) 02:58, 18 May 2016 (UTC)

sudo vim yourfilename results in sudo: vim: command not found. Thank you for the tip on creating symlinks, which I will try if advice is that I need to do the move. At this stage, I don't know whether I need to or not. Akld guy (talk) 03:13, 18 May 2016 (UTC)

@Scs: Follow up: The Raspberry Pi (original model B) running Raspbian (a cut down version of Debian) does not behave according to Debian command lists. Some commands are inoperative. Thanks to those who responded. I'm going to erase the SD card, download Raspbian, and start again. Akld guy (talk) 17:47, 19 May 2016 (UTC) Edited Akld guy (talk) 05:05, 20 May 2016 (UTC)

Comprehensive listing of hex colors and hex color codes

I know that there are 16 raised to the 6th power (equaling nearly 17 million) hex colors and hex color codes. In other words, quite a lot. Is there any website that lists all or nearly all -- or even a real lot -- of them? Also, is there any website where I can type in the color code, and it will give me the name of the color? For example, I type in "2D5A8B" (or whatever) and it returns "light green" (or whatever)? I have checked out most (all?) of the relevant Wikipedia articles, I think. It's easy to find small samples and smatterings here and there. What I would ideally like is a list that starts at Color # 1 (which I guess is 000000) and lists all the way down to Color # 17 million (which I guess is FFFFFF). And it shows the incremental darkening (or lightening) of the color spectrum. Even if it does not do so by increments of "1" necessarily. In other words, it incrementally goes through all of the colors in order as they increase from light to dark (or vice versa). Thanks. Joseph A. Spadaro (talk) 04:08, 17 May 2016 (UTC)

Rather than having a list of 17 million, wouldn't it be easier if you type in the hex code and it generates the color ? StuRat (talk) 04:34, 17 May 2016 (UTC)

Yes, I could do so, but that misses the whole point. Joseph A. Spadaro (talk) 05:07, 17 May 2016 (UTC)

As far as typing in the hex code and it spitting out a name, it would either have to define ranges such that every hex code falls into one, or if each color name matches only a single hex code, then most hex codes would have no match. StuRat (talk) 04:37, 17 May 2016 (UTC)

I realize that there is likely no website that has all 17 million (each color raised by an increment of one). I am asking for the "next best thing", I guess. Joseph A. Spadaro (talk) 05:07, 17 May 2016 (UTC)

It's probably far from exhaustive but you could start with something like this.Vespine (talk) 06:54, 17 May 2016 (UTC)

This site will take a hex code and give you the "nearest" colour name - e.g. #FFFF00 is "yellow", #FFFF01 is "yellow (approx)". I haven't checked it thoroughly enough to know how accurate it is. AndrewWTaylor (talk) 06:58, 17 May 2016 (UTC)

This forum post has a 1049 byte PostScript file showing all 16777216 colours on 32768 pages. If you prefer pdf, you can convert it yourself to a 119MB pdf file, but in this case PostScript is definitely superior. PiusImpavidus (talk) 09:11, 17 May 2016 (UTC)

Thanks. But I did not understand that website (forum). I saw a bunch of computer code. What exactly am I supposed to do with that code? Thanks. Joseph A. Spadaro (talk) 16:15, 17 May 2016 (UTC)

Copy-paste to a text file, save with the extension .ps, open it in your favourite application for ps files. Here are some suggestions. PiusImpavidus (talk) 17:24, 17 May 2016 (UTC)

Sorry, this is all over my head. And I am not familiar with any of this. I can cut-and-paste that code and create a Word file? I didn't think that Word has other "extensions" like .ps? Joseph A. Spadaro (talk) 18:19, 17 May 2016 (UTC)

Pius didn't say "save it from Word", nor "open it in Word"; he said "open it in your favourite application for ps files," and pointed you to a list of such applications. (I just tried opening a .ps file in Word; it did not interpret the PS, only opened it as plain text.) —Tamfang (talk) 07:38, 18 May 2016 (UTC)

Yes. I don't have a "favorite application". I don't even know what a ps file is. And, on that list, I don't have any of those programs. And never even heard of any of them. The only program I am familiar with is Word. Joseph A. Spadaro (talk) 19:59, 18 May 2016 (UTC)

If you don't have any of those programs – do we need to explain downloading? A .ps file is a file of PostScript commands, as was kind of implied by PiiImpavidi first mention of "a PostScript file". —Tamfang (talk) 08:41, 19 May 2016 (UTC)

Wow, if the PS file is really only 1049 bytes, that's some 16000 colors per byte, it sure is superior ! :-) StuRat (talk) 15:15, 17 May 2016 (UTC)

That's because it doesn't list the colours directly, but has an algorithm to generate the list. Which is unlike the pdf you can generate from it, as pdf doesn't support procedures. PiusImpavidus (talk) 17:24, 17 May 2016 (UTC)

Most colors do NOT have names. The names are a result of old computer systems. If you go way back, early Unix systems defined a handful of colors: red, blue, yellow, green, black, white... and a few dark versions like darkred and darkgreen. Over time, a few light variants were added. Then, a worker wanted more colors, so we went to the local paint store and grabbed a sample book. He programmed the names/RGB values of all the colors in the sample book. Much later, a worker wanted even more named colors. So, he grabbed a box of crayons and programmed the names/RGB values of all the colors in the crayon box. Then, much much later, CSS adopted all the original, paint store, and crayon color names. As they were being added, the daughter of one of the CSS programmers died. So, they defined a color just for her. That was it. The dominant opinion was that people should not be using these silly color names. They should be using RGB values. So, anywhere you see a list of color names, you will usually see a disclaimer such as "If you use these names in a real project, everyone will laugh at you." Because use of the color names is not popular, there is very little intention to continue defining abstract names that really have no meaning. That is why you won't find a list of millions of names. 209.149.114.175 (talk) 12:30, 17 May 2016 (UTC)

I disagree. Code should be as easy to understand as possible, and using color names people can relate to helps here. StuRat (talk) 15:16, 17 May 2016 (UTC)

Oh, what was the daughter's name? —Tamfang (talk) 07:29, 18 May 2016 (UTC)

Her name was Rebecca. Her favorite color was purple. So, in CSS, they defined "rebeccapurple." 209.149.114.175 (talk) 13:42, 18 May 2016 (UTC)

It was Rebecca: see Eric A. Meyer. AndrewWTaylor (talk) 13:38, 18 May 2016 (UTC)

It would help if you could describe how you would intend to use these sites. Do you have a hex code to start with, and want to know what it looks like and what it's called ? Or do you want to use it in some other way ? StuRat (talk) 18:26, 17 May 2016 (UTC)

I guess the basic idea is this. I might be looking for a color that is sort of blue or sort of light green or whatever. So it would be nice to see an incrementral scale of the colors that are in the green family and very close in hex value (up and down). Also, when I see the colors all aligned in a row, it helps me to visualize and say, "Hey, maybe I don't want green after all. These colors in the orange family might be good for this project." Stuff like that. When I see colors all mixed together, willy-nilly, with no order or rhyme-and-reason (like this: List of colors (compact)), it's very unhelpful. I'd like a graded scale from dark to light, so I can see a color and its closest neighbors. Joseph A. Spadaro (talk) 20:11, 17 May 2016 (UTC)

It seems you're looking for a color tool. I don't know what's available for Windows, though. --Wrongfilter (talk) 20:22, 17 May 2016 (UTC)

Agreed. A 1-dimensional list (like varying the amount of blue) isn't good enough, since there are at least 3 parameters that vary in colors. A 2D chart is better, where you could vary 2 colors at once. So, you can have the amount of green vary from 0 to 255 in one direction and the amount of blue vary from 0 to 255 in the other direction. But, that still doesn't handle the 3rd color (red, in this case). You would need 256 such charts, each with it's own constant amount of the third color, to handle that. To fit this all on one page, maybe cut back to 16 levels of each color, then once you pick one, that can be expanded to show all 256 levels of colors near the one you picked. StuRat (talk) 20:32, 17 May 2016 (UTC)

The problem here is that computers aren't sentient or subjective. They have no way of knowing whether one colour "looks" like another. So there would have to be some sort of ranges defined how much a colour can differ from another to be considered "similar". These ranges have to be defined by a human, but there is no guarantee other humans will think of the same ranges. JIP | Talk 20:44, 17 May 2016 (UTC)

I don't follow. If one color differs in hex value by exactly a value of "one", isn't it pretty much guaranteed to be "similar"? For example, hex color code 2222222 and 2222221 differ by only an increment of "one". I assume those two colors must be very similar, practically identical. No? Wouldn't this be the same for any two colors that differ by only an increment of one? Joseph A. Spadaro (talk) 22:26, 17 May 2016 (UTC)

Yes, 1 will be only a slight variation, but in some cases people will be able to distinguish the variation, and not in others. It depends on the person, and also the color, as we are more sensitive to some colors than others. When asked, "is this color an orange", you would get very different answers from different people, like here: [1]. StuRat (talk) 22:41, 17 May 2016 (UTC)

Some might enjoy browsing https://allrgb.com/ —Tamfang (talk) 07:31, 18 May 2016 (UTC)

please recommend disk cloning software

Hi please recommend disk cloning software that is able to make a copy of an SSD boot drive to another SSD drive, and the target must be bootable and have all the Windows 10 system files of the source. Preferably not expensive. Norton Ghost is not an option as that is quite costly I believe, and this is a once-off exercise. Thanks. Sandman1142 (talk) 12:11, 17 May 2016 (UTC)

Clonezilla -- Finlay McWalter··–·Talk 12:59, 17 May 2016 (UTC)

Thanks but it gave me such a horrible error, I was too afraid to continue. I ended up using the copy and paste in GParted which worked well. Thanks guys! Sandman1142 (talk) 07:15, 19 May 2016 (UTC)

See [2] for a list; most of them come on live images so you can boot directly into them. PartImage is well regarded. LongHairedFop (talk) 18:58, 17 May 2016 (UTC)

See also List of disk cloning software, although I'm not sure how up to date it is.-gadfium 20:56, 17 May 2016 (UTC)

Oh and I ended up with the nice 1234F: prompt which was fixed with a lot of fiddling in testdisk. Thanks to the author of that brilliant software! Sandman1142 (talk) 07:56, 19 May 2016 (UTC)

Word spacing/indenting problems for my bibliography?

Hey wikipedians,

I am writing my bibliography for a paper (due soon!) and for just one of my entries I cannot get all the lines except the first one to be indented, as is required. Ctrl+t puts the entire entry all the way on the left, and spacing for the second line and under doesn't work at the beginning of the line. I am discombobulated and confused. — Preceding unsigned comment added by 140.233.173.11 (talk) 12:28, 17 May 2016 (UTC)

What program are you using to type your bibliography? 209.149.114.175 (talk) 12:50, 17 May 2016 (UTC)

Sorry - word 2010 — Preceding unsigned comment added by 140.233.173.11 (talk) 12:58, 17 May 2016 (UTC)

Sounds like you need to set the left margin, not indent. Indeed, if you try to indent anything but the first line of a paragraph, it will probably try to "correct" it. There may be two places to change the margins, once for the screen display margins and another for the print margins. Alternatively, if you don't have time to learn Word 2010, you could use a simpler word processor, like NotePad, which lets you manually space things out however you want. You could cut and paste into it. StuRat (talk) 14:33, 17 May 2016 (UTC)

Thanks! I got it to work. — Preceding unsigned comment added by 140.233.173.11 (talk) 15:21, 17 May 2016 (UTC)

Resolved

StuRat (talk) 16:11, 17 May 2016 (UTC)

BBC Food Website

The BBC have announced that they are removing the index to their recipe pages, and it seems they're removing them from web searches (see here). But they're not removing the actual recipes. How does this save them anything? Rojomoke (talk) 17:06, 17 May 2016 (UTC)

That link says they did it for political reasons (literally, because politicians complained that they were spreading beyond their government mandate and competing with businesses). Sounds like they will make it inconvenient for anyone to find a recipe, but will leave them there for anyone who has links from their page to an existing recipe. Seems a bit silly to me, too, though. StuRat (talk) 18:12, 17 May 2016 (UTC)

Smells a bit fishy.--178.106.99.31 (talk) 22:00, 17 May 2016 (UTC)

For those outside of BBC-related politics, this is a common complaint. Recently, some douche suggested that Doctor Who be banned from prime time television slots because it is a BBC show and it unfairly competes with commercial television (wow, there's actually a reference for this obnoxious claim!). So, basically, if the BBC does anything successful, someone complains that it competes with commercial businesses and the success must be somehow artificially dampened. 209.149.114.175 (talk) 13:32, 18 May 2016 (UTC)

The argument itself is sound, it's the "retroactive fix" nature that's the problem. If the BBC had, all along, been not allowed to do cooking and entertainment programs, and was limited to news and education, so as to not compete outside those areas, that would make sense. But to go back and wipe out what the taxpayers have already paid for makes about as much sense as destroying a government-built bridge, in perfect working order, so a private company can rebuild it for profit. StuRat (talk) 15:42, 18 May 2016 (UTC)

They have since listened to the public outcry and will move the recipes to their Good Food website. 86.28.195.109 (talk) 06:45, 18 May 2016 (UTC)