Software

People who would never walk into a store and shoplift a software product think nothing of making several copies of the same software. The results are the same. This act is just as wrong. When it comes to unauthorized duplication of software, many people do not realize the costly impact on the software developer and the customer community. The relationship between customer and developer in a software transaction is one of mutual trust. The customer trusts that the developer has produced a product that will deliver the desired result, performs according to specifications, and is properly documented and supported. The developer trusts that the customer will make use of only those copies for which he has purchased a license, even though making additional, unauthorized copies is relatively easy. Unauthorized duplication and use of software violates the U.S. Copyright Law, and it unfairly deprives software developers of revenue they are entitled to receive for their work. Software developers find that thousands of illegal copies have been made by customers who either innocently believe they are doing nothing wrong or simply choose to ignore the law.

Reproducing computer software without authorization violates the U.S. Copyright Law. It is a Federal offense. The money paid for a software product represents a license fee for the use of one copy. It does not represent an authorization to copy. Civil damages for unauthorized software copying can be as much as $50,000 or more, and criminal penalties include fines of up to $100,000 and imprisonment of up to five years.

Let’s start by dispelling some myths with a few facts.

First, software developers do not condone unauthorized copying in order to gain market penetration.

Second, the price of software does not make unauthorized copying justifiable. The cost of a software product to a consumer represents only a small fraction of the publisher’s development and marketing cost.

Third, although the cost of softlifting (installing a licensed copy on more than one machine) is borne initially by the software developer, it is paid for ultimately by legitimate users.

It’s obvious that legitimate software users are paying for theft along with software developers. It’s obvious, too, that no one is going to put up with it for long. Think twice before you ask someone to give you an illegal copy of their software. Think three times before you offer to do it for someone else. Softlifting or software piracy is not only a crime; it’s simply wrong.

Reviewed by John Sopko 6/17/2014

The campus has purchased a campus wide license for Mathematica software by Wolfram. Most department Windows machines come pre-installed with Mathematica.  If you have a Linux Machine or a Windows machine and need Matlab installed, please send email to help@cs-old.sites.unc.edu with the name of your machine.  See the campus Mathematica help page for more information on Mathematica.

If you are a student with a computer not owned by the Computer Science Department, you can install Mathematica on that machine.  Follow the instructions on the campus Mathematica help page to obtain and install Mathematica.

Reviewed by Murray Anderegg 02/27/2013

Emacs is a large and powerful text editor commonly used by programmers.  It is a locally installed package on department Linux machines, and it is maintained by the GNU project with a home page at http://www.gnu.org/software/emacs/.  Following is information on starting emacs, obtaining online help, basic text entry, and using the Meta key.

Starting emacs

To start emacs on a Linux system, type “emacs”.

If you are interested in using emacs, run the tutorial to get basic information.  The tutorial is accessed by typing “Ctrl-h t” (that is, hold down the “control” key and, while holding it down, press “h”.  Then release both keys and press “t”).  The emacs tutorial is quite comprehensive and is recommended as a good way for a new emacs user to become familiar with emacs basics.

Obtaining online help

To get online help, type “Ctrl-h i” (that is, hold down the “control” key and, while holding it down, press “h”.  Then release both keys and press “i”).  There are also man pages (“man emacs”).

Basic text entry
To enter text, just type it in.  Some simple functions:

quit: Ctrl-x Ctrl-c (automtically prompts to save your file).

cursor movement:
up: up arrow or Ctrl-p (“previous”)
down: down arrow or Ctrl-n (“next”)
left: left arrow or Ctrl-b (“back”)
right: right arrow or Ctrl-f (“forward”)

page forward: Ctrl-v
page backward: Esc v

search forward: ctrl-s (simply repeat to use last search target)
global-replace-with-confirm: Esc %

Using the Meta key

If you run emacs in an X environment and you have your DISPLAY environment variable set, emacs will by default bring up its own window.  In the X environment, you can enter all commands starting with Esc by holding down the Meta key type % and hitting the second character of the command.  (The Meta key is different depending on your keyboard and is generally next to the space bar; it may be the Alt, Windows, Macintosh command key.)  For example, to enter the command Esc %, you would hold down the Meta key and then the % key.  You are not required to do this; it is merely another option to using the Esc key.

Reviewed by Bil Hays on 7/25/2013.

Clamav is a free and open source virus scanning tool. For personal use Installing clamav is pretty straightforward, there’s a version that runs in user space:

sudo apt-get install clamav

Run freshclam to update the signatures:

sudo freshclam

Then to scan the system, use clamscan.

clamscan -r --bell -i /afs/cs-old.sites.unc.edu/home/hays

The command above will scan my home directory, all files recursively, and it will ring the bell if it finds an infected file. If you want to scan the entire system, you’ll need to run clamscan with sudo. If you’re doing that on a machine that runs afs, you’ll also want to exclude /afs:

sudo clamscan -r --bell -i --exclude="/afs" /

If you would like to use a GUI for running clamav, install clamtk. It’s a good option in that you can use it to schedule regular scans if you’re not comfortable with the command line and cron, and it give you easy access to the basic functionality. To set a scheduled scan, open clamtk and press Ctrl-t to open the advanced settings menu.

Depending on how you use your computer, you may find some false positives. The best thing to do in that case is whitelist those files. Once you’re run a few scans and have what you need whitelisted, then you can make a folder called quarantine, and run clamav to move infected files there.

clamscan -r --bell -i --move=/afs/cs-old.sites.unc.edu/home/hays/quarantine /afs/cs-old.sites.unc.edu/home/hays

Obviously, false positive can be a real problem. Perl modules in cpan and javascript files may be tagged as problems, so use the quarantine option with care.

If you’d like to test this or other anti-virus software you can get a fake malware sample from eicar.