So, we now know our way around the Unix filesystem now and we know how to read, move or delete files. We also know how to ask for help if we’re stuck. This post in the Unix 101 series will teach you about file permissions.
We’ve been talking about Unix being a multi-user, multiprocessing system, but we haven’t really though of security yet, have we ? I mean, if there are several users using a system at the same time, your personal data can’t be safe, right ?
Wrong !
The designers of …

This post is the next in a series of posts we’re doing on Unix. The aim of the series is to get our readers familiar with the basics of working on a Unix or a Linux system.
Uptil now we’ve learned a bit about how the Unix system works and how to navigate around the filesystem. We can now login to a unix system and start viewing the files and moving around between different directories. We also know a little about processes on a Unix system.
What next ?
This post will teach …

According to wikipedia, a filesystem is:
is a method for storing and organizing computer files and the data they contain to make it easy to find and access them.
It is the filesystem which provides us the abstraction of folders, directories and sub-directories that we use to store files on a computer. Infact, it is the filesystem only which lets us store and retrieve any data that we store in a computer.
Filesystems are usually a part of the kernel, the heart of the operating system and the code runs in a privileged …

I’m sure you’ve heard people tell you that Unix (and Linux) is a multiuser/multitasking operating system. But, what does that mean ?
Well, for one, you can create multiple users on linux and let all of them use the machine at the same time, by letting them login remotely (We’ll cover this later). And thus, Linux is a multiuser operating system.
Multitasking is a little more complicated.
You see, a Unix system at any time is always running more than one programs simultaneously. Ah, but I am only running my browser, you ask …

“UNIX is basically a simple operating system, but you have to be a genius to understand the simplicity.”
- Dennis Ritchie
Dennis Ritchie is one of the creators of Unix and the above quote summarizes the philosophy behind Unix. The Unix command line is terse by design and it can take a new user a long time to understand (and remember) the nuances of a particular command line.
Fret not, cause man is at hand.
man is the unix/linux command line utility designed to display documentation about a given command. For example, suppose you’ve …

In the last post of this series, we learned about logging in to a Linux box, creating a new non superuser account and start using that.
In this post we’ll learn how to start working with files. Creating, deleting and managing files is the reason you use a computer, right ?
Unix has a concept of directories, which is the same as a folder on Windows.
To list all the files in the current directory, use the following command:
$ ls
This will give you a list of directories in what is called the wide …

I have a confession to make. I’m a Unix guy, have always been and will always be. I’ve been using Unix for the last 10 years or so and will continue using it for as long as I can. There is something about the simplicity of the unix command line that none of the flashier operating systems can match.
I’ve also been interviewing people with basic Unix skills for various positions over the last couple of years. For some reason, I’ve found that Indian college curriculum doesn’t put too much emphasis …