File permissions are one of the strengths that the Unix world has had over it's Windows contemporaries. Permissions are a means to control access to information on a computer, on a file by file basis. There are several layers of control, and these will be discussed below.
For the purpose of this series of tutorials, I have been using a free FTP program called Core FTP Lite to upload files to my server. I am using this program to describe my examples.
Ok, to begin, let's say that we have uploaded some files to a server.
We are discussing uploading scripts in general here, and certainly for many scripts, the creators may well specify certain 'permissions' that need to be set in order for the scripts to operate correctly. Let's take a look at a set of files on a server. In Core FTP Lite, the server files are shown in the right hand pane. Select one and then right click on the highlighted file.If you use a different FTP client, I expect that the layout will be very similar.
Run the mouse down to the bottom of the menu and select the item marked 'Properties'. Click on this option, and another dialog will appear.
You will see that the file in question (in this case a directory) is being shown in the 'File' field at the top of the screen.
What we are really interested in, is the tick boxes in the bottom half of the screen. These hold the file 'privileges' or 'permissions' for this file or directory.
There are three types of 'permissions' available.
* User - which means the person signed on who is setting the permissions
* Group - which means a specific group of users for whom access to the file has been granted
* World - which means everyone.
Within these groups of users, there are 3 distinct types of permissions
* Read - which means that permission to read a file, but not alter it or run it
* Write - which means permission to write to a file and change it
* Execute - which means permission to execute a file, which is important in the case of scripts for example.
Permissions are sometimes called by these names (read, write, execute) but are more commonly referred to using letters 'rwx'. In addition, permissions are sometimes referred to by a single number '755' for example. In the picture above, you will see a value box. This is the number being referred to. How is this number made up? Well let me explain.
Read
User 400
Group 40
World 4
Write
User 200
Group 20
World 2
Execute
User 100
Group 10
World 1
Each value for each setting is shown. Try them out by ticking them, and see the number in the 'Value' field change accordingly.
So, lets look at a real example
Can you see how the number 755 is made up? Add up the individual values from the value table and see.
So hopefully you can see, that setting file permissions with the right tool is not hard at all.
Charlie Cory worked or many years running a HelpDesk for a software house, and has experience in many operatng systems and technologies. The online aticle contains many pictures which help bring this tutorial to life.
Stop Getting LostOne of the greatest uses for a pocket... Read More
Simone is exasperated. She has to work on her university... Read More
After another security hole recently surfaced in Microsoft's Windows operating... Read More
Tip #1. Do a Google search. Don't be to general... Read More
In the first part of this home lab tutorial, CCNA... Read More
By using your computer today you can find a lot... Read More
You use Ctrl+Alt+Del to see what's running on your PC,... Read More
This is not your typical lost data story. I was... Read More
"Aaaaaahhhhhh! I've been invaded by a virus!" Getting a virus... Read More
Computers are available in different shapes, sizes and weights, due... Read More
If you are a building a website or a forum,... Read More
I have a p3 500MHz PC with 128MB RAM, 10.2... Read More
HTTP ProtocolThe web is run on port 80. You are... Read More
Yes, it's true. You may have inadvertently invited a spy... Read More
As the web has evolved, so have the methods of... Read More
When you think of a help desk, what do you... Read More
Spyware is the software that collects information about your online... Read More
Flow Text Around a GraphicQuestion: I have inserted a photo... Read More
Has This Ever Happened To You? OK.. it's Friday night,... Read More
The battle is heating up for market share, home movie... Read More
I would like to tell you about a magic home.... Read More
Using SQL Server 2000 and above versions you can retrieve... Read More
Occupational Therapy Made EasierMedical downloads for the pda have improved... Read More
Peoples' private information needs to stay private, even after it... Read More
With a little tweaking and with proper tools, you can... Read More
Most of the web applications have a lot of images... Read More
I have a p3 500MHz PC with 128MB RAM, 10.2... Read More
I recently took a good look at what was keeping... Read More
Are you looking for an MP3 player but am not... Read More
Spyware is the software that collects information about your online... Read More
Passwords have a strange dual nature. The stronger and safer... Read More
About mail-mergingMail-merging is the process of merging variable data and... Read More
You will need the following:1. 1.44MB FDD (floppy)2. NVFLASH utility... Read More
When browsing the internet you are likely to come across... Read More
On 21 August 2003 Symantec Security Response upgraded the W32.SOBIG.F... Read More
Up until the recent past, those who wanted to take... Read More
All over the world, people carry with them walkmans and... Read More
Enhanced Definition Television ? also known as EDTV ? is... Read More
One of the most common questions computer users ask is,... Read More
When you think of a help desk, what do you... Read More
As the owner of a Country Mall and Top Site... Read More
The battle is heating up for market share, home movie... Read More
If you are a building a website or a forum,... Read More
Do you use Windows standard uninstall feature? How do you... Read More
Feeling overwhelmed in selecting a new TV? With all the... Read More
With the new technology used to transfer information to from... Read More
Do you know how many fonts are currently installed on... Read More
Get started creating web pages using text files and HTML... Read More
You probably heard of the new Firefox browser version 1.0... Read More
Apache, MysQL and PHP for Windows could be a nice... Read More
Personal Technology |