Bango

Imagine that you got three lovely cute and growing children, and you got only one PC at your home. You went to your office as usual and went home late at night. You turn your PC on. Logging in to your account and suddenly.... Hey..!!! Where is my data? Where is my MS Office?. Your data is lost and your MS Office is uninstalled. By who? Needles to say, your children did the job. They accidentally erased your files and uninstall your software.

That is just and illustrated story if we are in the Windows world. Since it has no protection against file rights. Files is just files. They just wrote to your hard drive with some information like its size, last accessed time, and the type of that files. In Unix and Linux world, all hardware and software are treated as files. Look under directory /dev and you will see huge list of hardware list over there.

What about protection? In Linux world we got something called file permission. It ensures that only the right user can read, write, or execute the files. Give an ls -l command in the console and it explain a lot.

Here is the output on my console :

salon@Presario:~$ ls -l
total 835508
-rw-r--r-- 1 salon users 539079 2007-11-11 20:14 118262253_fb1db4700e_b.jpg
-rw-r--r-- 1 salon users 109954 2007-11-07 10:41 22030-Ubuntu-Smooth-Splash.tar.gz
-rw-r--r-- 1 salon users 52973 2007-11-07 10:31 36907-Blu.xpm.gz
-rw-r--r-- 1 salon users 212215 2007-11-04 23:46 4x4offroads-12-1280.jpg
-rw-r--r-- 1 salon users 235112 2007-11-04 23:48 4x4offroads-16-1280.jpg
-rw-r--r-- 1 salon users 217260 2007-11-04 23:48 4x4offroads-17-1280.jpg

Notice that rw-r--r-- sign. What the hell is it? For easy understanding read carefully below :

rw- means that the owner of the file, in this case salon has the right to read and write the file
r-- means that all of the groups member, in this case users group, can only read the file
r-- means other than the owner and the groups members can only read the file

You can also modify the bit by using chmod command. Issuing command chmod 700 (somefiles) would change the permission so only the owner of the files can access it. But i don't like back to DOS world by typing those commands. Easy, just fire up Nautilus and right click to the file you want to modify. Choose properties and click permission tab. Change it the way you like.

So now you just change the permission of your data folder and you don't have to worry again. Good Luck.