Wikipedia:Reference desk/Archives/Computing/2010 February 1

= February 1 =

What file compression format has the smallest minimum size?
What file compression format has the smallest minimum size file? I'm not asking about the efficiency of compression, but rather the minimum "footprint" of an archive. For example, (these are made up numbers) a ZIP archive of a 100B file would still need 20KB of disk space just to create the ZIP container. --70.167.58.6 (talk) 00:20, 1 February 2010 (UTC)
 * Does it include the size of the program needed to de-compress the files as well?Shortfatlad (talk) 00:27, 1 February 2010 (UTC)
 * A trivial compression algorithm could be extremely small. For instance, converting any run of 3 or more words (words being whatever unit you're using in the algorithm, such as hex words) into some code of word plus repeat count.


 * I think what you want is what widely available useful compression algorithm would have a small footprint. This post might help you for a practical example. From that discussion it looks like zlib family compression algorithms have good overhead properties. Shadowjams (talk) 00:50, 1 February 2010 (UTC)


 * There are compression programs with no overhead at all, such as bicom. It compresses a file of length zero to a file of length zero. -- BenRG (talk) 02:50, 1 February 2010 (UTC)

minimum qualification for post of lecturer in degree colleges
hi,

wheather it is mandatory for a person with M.C.A degree to become lecturer in degree colleges to pass NET/SLET/PHD ?

thanking u

bye Nagendra R —Preceding unsigned comment added by Siranagendra (talk • contribs) 05:50, 1 February 2010 (UTC)


 * This question has come up multiple times. It depends on the country.  In the United States, a Masters Degree is all that is usually necessary, but most universities want PhDs. --  k a i n a w &trade; 05:56, 1 February 2010 (UTC)

DjVu file download
1) I would like to save a copy of the DjVu file from this page http://www.archive.org/details/tenacresenoughpr00morriala but right clicking and saving the DjVu link does nopt work, and the DjVu reader itself does not offer any means of saving it to HD. How could I save it please? I have tried using CacheViewer and PageInfo from Firefox, but neither of them show a DjVu file. 2) Why is the DjVu file so much smaller than the Pdf file? Thanks 84.13.23.254 (talk) 13:54, 1 February 2010 (UTC)


 * Click on "All Files: HTTP", then right-click, save-as the DjVu file at the top of the list. I don't know why, but the regular DjVu link is only set up to "stream", whereas the "All files" link lets you just download the individual files, no questions asked. --Mr.98 (talk) 15:11, 1 February 2010 (UTC)

Java to retrieve webpage source
Hello again! Could someone please give me a Java code example that retrieves a source of a webpage given a web address, so that I can apply a Scanner to it to look for certain words? Thank you!--el Aprel (facta-facienda) 17:27, 1 February 2010 (UTC)
 * See the archives, where I did this (mostly for fun). --Tardis (talk) 18:19, 1 February 2010 (UTC)
 * (edit conflict) This page shows how to open a internet connection (for reading etc) http://java.sun.com/docs/books/tutorial/networking/urls/readingWriting.html as used in the above example, this one http://java.sun.com/docs/books/tutorial/networking/urls/readingURL.html is all you need if you aren't writing back.
 * This page (about 1/2 way down for the code) - has another example of the same thing, and uses scanner class too - with emphasis on reading the whole page at once.
 * More info http://weblogs.java.net/blog/2004/10/24/stupid-scanner-tricks - this is probably the clearest and most concise. (though it's not clear to me why they use the \A instead of \Z regex to find the end of file.)
 * (or just save the web page as a .txt file to the hard disk and do as normal?) - do you want more glue? 87.102.67.84 (talk) 18:40, 1 February 2010 (UTC)
 * Good stuff—just what I needed. Thank you both!--el Aprel (facta-facienda) 21:59, 1 February 2010 (UTC)

Scan cancelled; no items to scan
I recently had error messages when I tried to visit Norton tech support, so I copied those messages and asked about them as a separate issue. I was told the exisitng software was corrupted and that I should download Norton's latest version. After I did, it wouldn't automatically do a full system scan like the old software did. I got a message worded essentially the same as the title of this section. If I clicked on the Norton logo and clicked on "scan", though, I could select a full system scan (the old software made that option harder to find) and it would do it. I asked Norton and couldn't get a straight answer or an obvious reason for this. There were no virus defintions when I first downloaded, and when I clicked on the Norton logo I got a red message saying I needed to take action, and over the next few hours I downloaded the virus definitions. That has not solved the problem of the scan not happening automatically, though the message telling me the scan was cancelled does pop up at the scheduled time to remind me to manually do the scan, which serves the purpose. It just seems strange. Vchimpanzee ·  talk  ·  contributions  · 18:44, 1 February 2010 (UTC)
 * Sounds like the new norton has inherited an issue from the old norton - maybe because the old norton wasn't fully uninstalled when you uploaded the new norton. (I believe norton has tools to fully uninstall an old version - did you use anything like that? eg )87.102.67.84 (talk) 19:10, 1 February 2010 (UTC)
 * I'm not sure. I uninstalled the old version when it told me to. I have a couple of other Norton products that I downloaded free to help me with the problem I contacted them about (which most people say was a fake virus message anyway), but I think they operate independently. The one that does the scan is operating continuously, while the others just run when I tell them to. Vchimpanzee ·  talk  ·  contributions  · 19:23, 1 February 2010 (UTC)
 * If you want to start afresh there's a guide here - - what it says is right - in that after uninstalling norton there's still a lot left. Is it right that you are getting the same (erroneous) popup from the old norton even though you've got new norton - if so I would recommend the total uninstall - both two links above, restart and then reinstall. (it's just a minor bug though isn't it?)87.102.67.84 (talk) 19:31, 1 February 2010 (UTC)
 * I never saw a message saying "Scan cancelled" until I got the new software. I'm not aware the error messages I reported had any effect on Norton's performance.


 * This is a copy of the message I sent to Norton that led to the downloading of updated software. I've replaced my real name with my name on Wikipedia.


 * I clicked on "Help and Support". At the end of the first step I got this message: "Autofix did not find any issues that affect your Norton Internet security and performance". But before that, a box popped up with the following error messages (my computer has no backslash key so I used the forward slash)


 * (01)6947=No Smartissue template file specified.
 * (02)6961=Invalid Smartissue template -Parsing XML Error: no element found File C:/Users/Vchimpanzee/AppData/local/Temp/siA0B4.tmp Line: 1 Column: 0
 * (03) 536870914=Unable to copy file C;/Users/Vchimpanzee/AppData/Local/Temp_tf1E7.tmp->C:/Users/Vchimpanzee/AppData/Local/Temp/siF604.tmp
 * (04)2=The system cannot find the file specified.


 * When I clicked on "OK" and the first box disappeared, there was a new one: Function:startXMLIO.js.cfm Name: Error Message: (01)6951=Failed to open file []. Description: (01)6951: Failed to open file[]. Vchimpanzee ·  talk  ·  contributions  · 20:19, 1 February 2010 (UTC)
 * Sorry I misunderstood - obviously your version of norton has a bug. You could try the clean install method anyway - but it may not help.
 * I's suggest re-contacting norton support and ask them for a version that actually works as intended. I don't think it will be possible for anyone here to debug the whole thing, and it's probably restricted to do so in the terms of service.87.102.67.84 (talk) 09:31, 2 February 2010 (UTC)


 * Without wanting to panic you, it's said that attacking (and disabling) norton is one thing some viruses will try to do. (It still may be norton's incompetence that is causing your problem).
 * Whilst you wait for them to fix it you could use Microsoft Security Essentials or something else free in the interim period.87.102.67.84 (talk) 10:24, 2 February 2010 (UTC)


 * A minor remark: the directory separator character on the Microsoft Windows platform is "\", not "/" as on the Internet. --Andreas Rejbrand (talk) 15:07, 2 February 2010 (UTC)


 * I didn't know how to make a backslash and I made a point of mentioning that, but maybe some will miss this. I've already informed Norton that when my subscription is up, I'll go with my Internet provider's McAfee software. I'm sure the scans are working but they just won't start automatically, though while I went to a funeral I noticed it was doing an idle time scan, so I guess it can start on its own. Vchimpanzee ·  talk  ·  contributions  · 15:57, 2 February 2010 (UTC)


 * Oh, yes, I am sorry; I did not see that (try charmap.exe). --Andreas Rejbrand (talk) 16:17, 2 February 2010 (UTC)

Mac Program Similar to Notepad++ (Not XCode)
Is there anything for the Mac OS X that is similar to Notepad++ that is not Xcode, which I view as too complicated. I like the former because it highlights similar tags and also colors tags red when invalid. I am only trying to do HTML, XHTML, CSS, and maybe JavaScript, so I don't want something too complicated. —Preceding unsigned comment added by 128.54.237.250 (talk) 21:46, 1 February 2010 (UTC)


 * I really enjoy TextWrangler. It is in that wonderful sweet spot of light-weight but feature-rich (and free). Syntax highlighting, but it doesn't tell you when things are wrong, I don't think. (But it doesn't highlight them, which is an indication.) Here is a list of a few other Mac-specific text editors. (Of course, the cross-platform ones should work too in some cases.) Of those, the others that look like they might fit the bill (though I haven't myself used them) are TextMate and skEdit, both of which cost money. --Mr.98 (talk) 23:10, 1 February 2010 (UTC)


 * I love Komodo Edit. It has all kinds of languages that it supports natively, and anything you can jury rig too. Oh, and it's free and free Quintus π  talk 23:34, 1 February 2010 (UTC)
 * Emacs, of course. Your Mac actually is a useful Unix computer under all that glitter (typed on a MacBook Pro ;-). And, of course Ed is the standard text editor. --Stephan Schulz (talk) 23:36, 1 February 2010 (UTC)
 * How about Notepad++? The article mentions that it runs on Wine on OS X. (OS X, incidentally, is not Unix. It's Mach with a Posix layer on top. Might as well have a Win32 layer too.) -- BenRG (talk) 09:34, 2 February 2010 (UTC)
 * Actually, MacOS-X officially is a UNIX. See Single_UNIX_Specification. It's not genetically UNIX at the kernel level, but much of the Userland is BSD-derived. It's certainly more UNIX than Linux (let the flames begin). --Stephan Schulz (talk) 11:05, 2 February 2010 (UTC)
 * I didn't realize that the Open Group had rebranded POSIX compliance as "real UNIX". I think that Windows 7 is real UNIX by that definition too, since it ships with Interix. I'm not sure why it's not on the list. But neither OS has much in common with UNIX, the operating system from AT&T. They just provide enough kernel support to implement POSIX (or Win32) in user mode libraries. Linux, despite being less POSIX-compliant than NT or Mach, at least has a UNIX-like system call interface. -- BenRG (talk) 20:28, 4 February 2010 (UTC)
 * No, POSIX is only a subset of the various UNIX specifications (UNIX98, UNIX03,...). And the Mach microkernel in MacOS-X does have a "BSD personality" (i.e. a system call interface that mimics FreeBSD fairly closely). You might want to argue that BSD is not a real UNIX, but that might lead to lengthy flamewars - see Ship of Theseus. Moreover, in contrast to Win7 (I think), MacOS-X actually ships with a fairly complete UNIX userland - sh, grep, awk, find, the works. --Stephan Schulz (talk) 00:01, 5 February 2010 (UTC)
 * I used Taco HTML Edit when I did HTML stuff. Not sure if it does JavaScript. I also think it's now shareware, which is a pain. Brammers (talk) 13:01, 2 February 2010 (UTC)

I went with TextWrangler for various reasons. I like it except for one aspect... Is there any way to open a browser from within the program?--128.54.237.250 (talk) 06:08, 3 February 2010 (UTC)
 * The only two OS X text editors I can think of with site preview features are Coda and Taco HTML Edit. Both have built in preview functionality.  Both are not free though being $100 and $25 respectively. Caltsar (talk) 21:36, 3 February 2010 (UTC)
 * Thanks. I need the freeware though. I think I made a good simple decision. --128.54.237.250 (talk) 23:59, 3 February 2010 (UTC)
 * You can set it up to do this with a little Applescript: . --Mr.98 (talk) 01:37, 4 February 2010 (UTC)