Wikipedia:Reference desk/Archives/Computing/2012 August 21

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August 21

Tandy Color Computer Emulators & .ccc files

I have so far searched in vain for a Tandy Color Computer Emulator that will run on my Windows 7 System and recognize ROM files with a .ccc file extension. Can someone help me here? 69.120.136.162 (talk) 06:29, 21 August 2012 (UTC)

To answer your question, in any of the emulators just change the extension to".rom" for some and ".pak" for others. All the rompaks are basically the same. Just the extensions are diffewrent. Bp

commandline arguements in c

Hi sir!My dout is about command line arguments in c language. 1)we can execute a c program after getting .exe file of that program.then what is the speciality of command line arguments. 2)by using command line arguments we are giving input from command prompt to main. We can use the arguments passed to main in our programme.we can pass data required by programme with out using command line arguments.then why should we send data to main()?what is use,speciality and need of command line arguements? Sir!please explain with an example. I hope you help me. — Preceding unsigned comment added by Phanihup (talk • contribs) 11:58, 21 August 2012 (UTC)

http://webchat.freenode.net/?nick=Phanihup&channels=#friendly-coders ¦ Reisio (talk) 13:48, 21 August 2012 (UTC)

No idea what Reisio is getting at with the above IRC link.

To answer the question: Command line arguments can be passed to main like this: main(int argc, char *argv[]) where argc is a count of tyhe number of arguments and argv is a list of the argument values. By convention argv[0] is the command used to start the program. They are used to pass all kinds of data to the program when it is run from a terminal, things like configuration values, filenames, paths, and so on. This saves having to have an interactive prompt for each piece of data and simplifies running the program from a script that might do all kinds of pre and post-processing around the program itself. It can also be important to be able to separate the running of the program from a GUI driven program launching mechanism, particularly when testing or debugging.

So, for example, only today I needed to run a program I had modified in debug mode. I could have done this from the GUI launcher, but I would have had to install the GUI and then think of a way to attach to the running program in gdb before it got too far. Instead, using the command line, I could simply run the program from gdb supplying the necessary startup data on the command line.

Another example: Elsewhere in my work, we have many complex scripts that start a sequence of processing that uses many programs. Each program passes data to the next using temporary files whose names are passed in the command line arguments - a typical example here is customer invoicing pulling data from many data sources. The scripts are scheduled to run at specific time in crontab. The advantage of this is that this time consuming process all happens out of hours with no human intervention, and the resulting data is ready for the rest of the business to get working on in the morning.

You see, not every program that is important to a business requires a flashy GUI interface or even human interaction to do its thing. Astronaut (talk) 16:23, 22 August 2012 (UTC)

Where do Web Fonts live in the latest Firefox

When you go to a page that uses Web Fonts while using the latest Firefox browser, where does that font get put in Firefox? I've gone to a page that uses web fonts and then looked in %appdata%\Mozilla\Firefox and everything below, and found nothing. (using Windows 7 OS) 20.137.18.53 (talk) 12:27, 21 August 2012 (UTC)

Assuming it's the same from November 2011:

"On my system (Unix) they're stored at ~/.mozilla/default/Cache/A/AA/BBBBBBBB, where A is a (presumably random) alphanumeric directory, and B is a (presumably random) alphanumeric font file."…"On Windows they appear to be stored at C:\Users\yourUser\Local Settings\Application Data\Mozilla\Firefox\Profiles\yourFirefoxProfileName\Cache\A\AA\BBBBBBBB." — Wikipedia:Reference desk/Archives/Computing/2011_November_2#Web_Fonts_in_Firefox
If you just want to download them casually, there are a few extensions for making that easier. ¦ Reisio (talk) 13:46, 21 August 2012 (UTC)

Google Spreadsheet question

I'm trying to have a cell display "Today's starting count" where it takes the closing values from yesterday. If we were closed on the day before though it will display "NOVALUE" so what I want it to do is check the column that displays the previous day's closing count and IF there's no number there (because we were closed) then it scrolls up the column until it finds the most recent closing value and will return that value instead.

So far I've got IF(ISNUMBER(T1), T1, ) It's the last bit I don't know how to do. Any thoughts? Also if I set those T values to be preceded by a dollar sign, because they do represent money, will ISNUMBER still acknowledge it as a number?199.94.68.91 (talk) 19:50, 21 August 2012 (UTC)

I don't use Google spreadsheet, so I can't really answer your question, but, since no-one else has answered, may I suggest that you avoid the problem by just keeping a daily running total with zeros for your closed days? Dbfirs 06:51, 24 August 2012 (UTC)

All my locally stored e-mail is gone in Evolution after upgrading to Fedora 17

I decided to finally upgrade to Fedora 17 from Fedora 14. The old system was too old to update, so I had to do a full reinstall. Luckily I had kept my old home directory on a separate partition, and it seems to be intact. The first problem that struck me is at although Evolution seems to have retained my old e-mail account information, all the e-mail I had downloaded to my local hard drive is no longer accessible. Evolution just says it can't find the messages. I have the old versions of Evolution's mailbox files on my backup drive, but how can I use them in the new version of Evolution? Do I have to convert them somehow? JIP | Talk 20:12, 21 August 2012 (UTC)

It's probably a simple matter of copying the email data from your old drive to the specific correct place on the new drive (likely the same place), but I don't follow Evolution (and therefore don't know whether they've made drastic changes in that time span). You'd get this sorted much more rapidly on an IRC channel for Fedora or Linux in general (http://freenode.net/). ¦ Reisio (talk) 23:15, 21 August 2012 (UTC)

Further problems with Fedora 17

I've now sort of managed to get my old locally stored e-mail back in Evolution. I could get this year's received mail back, but not yet any of the previous years' (they were in subfolders of the old "Received mail" folder). But there's still some things I want to get sorted out.

My first sight at the new Gnome 3.0 desktop made me instantly agree with Linus Torvalds: "Gosh, this is horrible". I made Gnome force fallback mode, even though my system seems to be able to use the new desktop. But now I can't move the taskbars around any more, and most importantly, I can't add any quick launchers to the taskbars themselves, so I wouldn't have to use the menus. Is this at all possible?

I really can't understand the Gnome project's mentality. They seem to be thinking that the less the user can do with their computer, the better. I used to be able to move the taskbars around, add new launchers to them, move existing items on the taskbar around, and change the taskbars' colours. Now I can't do any of that any more. If it wasn't for fallback mode I wouldn't even have the taskbars any more. With the way this project is going, I wouldn't be surprised if the version of Gnome in Fedora 20 just offered two big buttons: "E-mail" and "World Wide Web". JIP | Talk 21:47, 21 August 2012 (UTC)

Try Xfce. ¦ Reisio (talk) 00:36, 22 August 2012 (UTC)

I noticed Cinnamon and installed it. Then when I logged out and logged back in, selecting "Cinnamon" as the session instead of "Gnome", I was very satisfied. Cinnamon is pretty much like Gnome, but with everything that Gnome 3 took away put back in. Can I now use it as my default session? JIP | Talk 18:54, 22 August 2012 (UTC)

No particular reason you couldn't. Linux Mint does, IIRC. ¦ Reisio (talk) 02:12, 23 August 2012 (UTC)

As well as that, the old Gnome Photo Viewer seems to be gone. In its place is "Shotwell Photo Manager", which seems to comply with the Gnome project's goal to destroy direct access to the computer's actual filesystem. I can't find any way to view thumbnails of all photos in a specific directory. Instead there's artificial constructs such as "Libraries" and "Tags". The old Photo Viewer offered a directory tree on the left-hand side and thumbnails of all images in the currently selected directory on the right-hand side. Is this possible in this new-fangled "Shotwell" thingy, or can I somehow get the old Photo Viewer back? JIP | Talk 20:39, 21 August 2012 (UTC)

The old Gnome photo viewer was called Eye of GNOME and should be in the package eog -- Finlay McWalterჷTalk 21:18, 21 August 2012 (UTC)

Yes, I still have Eye of Gnome, and it works, but it doesn't offer me a directory tree or a grid of thumbnail images. I think the program I used to use for this was called "gphoto". Is this available for Fedora 17? Shotwell Photo Manager seems to do pretty much the same thing, except instead of a directory tree, it offers me useless artificial constructs such as "libraries" or "tags". I can't find any way to make it show the physical directory tree on my hard drive. JIP | Talk 21:22, 21 August 2012 (UTC)

Sorry, never mind. The old program I was thinking of is "gthumb", not "gphoto". Although it doesn't show up in Fedora 17's "Add/Remove Software" menu, yum finds it, and after I installed it, it seems to work pretty much like before. I still have to configure it correctly. The mere fact that it offers me direct access to the directory structure instead of having to import pictures into an artificial "library" makes it my preferred viewer over Shotwell, hands-down. Now I still have to find out how to add quick launchers directly into the taskbar and if E-UAE and VICE exist as packages for Fedora 17 or do I have to compile them from the sources. JIP | Talk 21:36, 21 August 2012 (UTC)

Well, to be honest, Fedora 17 did do something right. Because Fedora 14 was too old to update, I had to do a full reinstall. This meant my old personal user account was gone. I had to create a new personal user account with the same username. I was expecting Fedora 17 to replace the old home directory with a new blank directory, and me having to restore my latest backup (luckily made minutes before the upgrade), and fiddle around with user ID and user name settings. But no, Fedora 17 happily informed me "A home directory with this user name already exists. Would you like Fedora to reuse this old home directory, updating all the user IDs and permissions so that all the files would belong to the new user?". I gladly selected "Yes, please!". And when I logged in to Fedora 17, my old home directory was there, with all the files, fully accessible. Now if I could only get the programs I've become accustomed to back... JIP | Talk 22:19, 21 August 2012 (UTC)

Too old to update doesn't really exist with free Unix systems (though so old it'd take less time to reinstall than to update does), as most of the software remains available for ages after it is obsolete. It's true it probably would've been smoother had you updated back when they'd have liked you to, but you could have done it still. It's also usually a trivial matter to list what packages you have currently installed, should you (for some truly valid reason) wish to reinstall. You can also essentially drop in a backed up /home/user/ directory's contents into a new install and have all your prefs just work, typically. Just FFR. ¦ Reisio (talk) 23:12, 21 August 2012 (UTC)

Install VICE and E-UAE on Fedora 17?

And still more problems with Fedora 17. The legacy computer emulators VICE and E-UAE are gone. Neither "Add/Remove Software" or yum can find them. Are these at all available for Fedora 17? Should I try compiling them from the sources? JIP | Talk 21:03, 21 August 2012 (UTC)

They're available via my distro's package manager, which means (given the popularity of the RPM format) that there are probably RPMs of them that you can install, whether Fedora provides them or not. ¦ Reisio (talk) 23:19, 21 August 2012 (UTC)

I found out that all I had to do was to install the free and non-free repository RPMs from RpmFusion. Now I could install both VICE and E-UAE with yum. And they work the same way as in Fedora 14, too. E-UAE still doesn't get the sound quite right. Do I need a faster computer or something? JIP | Talk 18:54, 22 August 2012 (UTC)

IME getting sound working well for emulating ancient systems is a matter of tweaking the configuration more than anything. Won't necessarily work just right out of the box. ¦ Reisio (talk) 02:11, 23 August 2012 (UTC)

Printing ink usage

If I use a cheap, absorbent paper, will that use more printer ink than, say, a glossy photo paper?--85.211.154.5 (talk) 21:38, 21 August 2012 (UTC)

I don't think so. The way inkjet printers work, the print head "spits" tiny drops of inks onto the paper--the paper doesn't suck the ink out of the print head. However, with uncoated, absorbent paper, much of the ink will be absorbed into the interior of the paper beneath the surface, resulting in less brilliant color. --173.49.10.157 (talk) 03:26, 22 August 2012 (UTC)

Note that many printers have settings for paper or media type, as well as printer quality in their drivers. Generally speaking, printing at higher quality uses more ink. As far as I know, so does printing on the glossy paper setting compared to plain paper. At least it seemed to on the Canon printers I've used based on what it looks like if you try printing with the glossy paper setting on plain paper. I believe this is to produce a higher quality print since the glossy paper can take more ink without smearing. I'm not sure how high quality matte paper compares to glossy. On Canon printers and I expect all printers with both pigment black ink and dye black ink, I believe dye ink is preferred when printing on glossy paper to pigment ink, possibly even when printing text. See also [1] (this appears to be from usenet, unfortunately I can't find a copy on Google Groups or somewhere else which doesn't mangle it as a forum post, perhaps because it wasn't supposed to be archived?), [2]. Nil Einne (talk) 12:06, 22 August 2012 (UTC)

Dots and slashes in internet addresses

Why do internet addresses have dots and slashes? Couldn't they ahve unified it? Instead of https://en.wikipedia.org/wiki/whatever we could have https..en.wikipedia.org.wiki.whatever or https://en/wikipedia/org/wiki/whatever. Comploose (talk) 23:00, 21 August 2012 (UTC)

One of the things Berners-Lee has stated he regrets not making happen. ¦ Reisio (talk) 23:06, 21 August 2012 (UTC)

I believe that his regret was using http:// instead of http:/, not making a distinction between paths and domains. See [3]. Paul (Stansifer) 00:23, 22 August 2012 (UTC)

"Why do internet addresses have dots and slashes?" he asked. :p You are correct (virtually) about the specifics of what he said. The slashes are unnecessary and so is having two standard delimiters (slashes and dots), and so is having two separate directions ([less.]more.MORE/less/less/less). ¦ Reisio (talk) 00:53, 22 August 2012 (UTC)

Well the colon seems to have originated with RFC 1738 (see URL), but the slash-dot notation for networking predates it. I believe the slash notation originated with early file systems. I'm unsure where the dot notation came from to refer to sub-domains, though. BigNate37_(T) 23:10, 21 August 2012 (UTC)

The notation allows us to uniquely specify communication. It distinguishes between several steps of the process of "asking" for a digital resource:

• URI scheme, or generic communications protocol; or, what language we will be speaking;
• user, or authentication; or, how we identify ourselves;
• host, or "server;" who is providing the service we will ask for, optionally using a globally-unique name;
• A uniquely qualified path to a resource
• Query string, an arbitrarily-complex refinement to what we are asking about.

These sub-parts are explained more formally and rigorously in our uniform resource identifier article. There are plenty of other ways to come up with an abstract, functionally-identical nomenclature and syntax for such requests. The URI had the advantage of being mostly human-readable, easy to parse by inspection, and still sophisticated enough to densely accomodate a lot of information. If the objective were strictly efficiency, we could use a 128-bit universally-unique IP address, and a universally-unique 256-bit resource-identifier, which would be completely unintelligible to any human; but could be trivially aliased by any convenient keyword or icon in a user's interface. It seems that users of the internet may be trending toward that direction, evidenced by the rise of indexed content. There is still merit to the idea that a human can deduce what a URL should be, from common sense, and locate a resource without searching or indexing; and the URI notation provides a syntax that makes such a use-case possible. Nimur (talk) 00:28, 22 August 2012 (UTC)

Well, they serve different purposes. The en.wikipedia.org identifies a domain; essentially "whom should I talk to?". The /wiki/Whatever is a path; it answers the question "what am I looking for?". The https:// is a protocol (in this case HTTPS, which transfers web pages securely); in other words, "how should I get it?". For more information, see URL#syntax. Paul (Stansifer) 00:21, 22 August 2012 (UTC)

The whole URL scheme is an arbitrary one (in the sense that you could easily replace it with something else of equivalent semantic content) dreamed up by geeks who never imagined that the whole world would be typing this stuff in on a regular basis. The fact that the average user still sees "http://" in front of every URL — despite having no clue what that means — is something of a colossal design failure. (Some browsers strip that stuff out and just handle it internally, which makes sense, given that your average person does not ever need to type in http:// or https:// manually.) --Mr.98 (talk) 00:25, 22 August 2012 (UTC)

Tibetan characters in Firefox under linux

In wikimedia.org/wikipedia/meta/wiki/List_of_Wikipedias, the only characters that do not show properly are the Tibetan. How can I correct that? Not that I care much, but I would want to know how it works. Comploose (talk) 23:17, 21 August 2012 (UTC)

The Tibetan languages article has a link to free fonts which support the letters used in Tibetan writing systems. Installing those should solve the problem. -- Finlay McWalterჷTalk 23:23, 21 August 2012 (UTC)