9 | ||(or) operator

Shell Scripting Tutorial


Hello Programmers, I’m Yash. Sole programmer at planetvearcity – a place where programmers come to learn, build, and grow.

Welcome to the tutorial series on shell scripting. In this video, we will learn how to use ||(or operator) in a shell script. It is really easy to use and understand this operator.

Just remember statement becomes true if at least one of the conditions is true.

Example: c1 || c2 || c3 || c4 : atleast one of the c1,c2, c3 or c4 must be true for the statement to be true.



8 | &&(and) operator

Shell Scripting Tutorial


Hello Programmers, I’m Yash. Sole programmer at planetvearcity – a place where programmers come to learn, build, and grow.

Welcome to the tutorial series on shell scripting. In this video, we will learn how to use &&(and operator) in shell script. It is really easy to use and understand this operator.

Just remember statement becomes true only if all the conditions are true otherwise it will be false.

Example: c1 && c2 && c3 && c4 : all c1, c2, c3 and c4 must be true for the statement to be true.



7 | file test operators

Shell Scripting Tutorial


Hello Programmers, I’m Yash. Sole programmer at planetvearcity – a place where programmers come to learn, build, and grow.

Welcome to the tutorial series on shell scripting. In this video, we will learn how to use a file condition operator along with if statement. There will be times when you will be dealing with files in your scripts. These operators make it easier for us to check conditions such as is file regular file, file exist or not, and much more.

– – – – File Test Operators – – – – –

The ones we will test:

a : True if the file exists.
e : True if the file exists.
d : True if the file exists and is a directory.
f : True if the file exists and is a regular file.
s : True if the file exists and has a size greater than zero.
r : True if the file exists and is readable.
w : True if the file exists and is writable.
x : True if the file exists and is executable.

The ones we will not test:

b : True if the file exists and is a block special file.
c : True if the file exists and is a character special file.
g : True if the file exists and its SGID bit is set.
h : True if the file exists and is a symbolic link.
k : True if the file exists and its sticky bit is set.
p : True if the file exists and is a named pipe (FIFO).
t : True if file descriptor is open and refers to a terminal.
u : True if the file exists and its SUID (set user ID) bit is set.
O : True if the file exists and is owned by the effective user ID.
G : True if the file exists and is owned by the effective group ID.
L : True if the file exists and is a symbolic link.
N : True if the file exists and has been modified since it was last read.
S : True if the file exists and is a socket.



6 | if statements

Shell Scripting Tutorial


Hello Programmers, I’m Yash. Sole programmer at planetvearcity – a place where programmers come to learn, build, and grow.

Welcome to the tutorial series on shell scripting. In this video, we will learn how to use a file condition operator along with if statement. There will be times when you will be dealing with files in your scripts. These operators make it easier for us to check conditions such as is file regular file, file exist or not, and much more.

– – – – File Test Opeartors – – – – –

The ones we will test:

a : True if the file exists.
e : True if the file exists.
d : True if the file exists and is a directory.
f : True if the file exists and is a regular file.
s : True if the file exists and has a size greater than zero.
r : True if the file exists and is readable.
w : True if the file exists and is writable.
x : True if the file exists and is executable.

The ones we will not test:

b : True if the file exists and is a block special file.
c : True if the file exists and is a character special file.
g : True if the file exists and its SGID bit is set.
h : True if the file exists and is a symbolic link.
k : True if the file exists and its sticky bit is set.
p : True if the file exists and is a named pipe (FIFO).
t : True if file descriptor is open and refers to a terminal.
u : True if the file exists and its SUID (set user ID) bit is set.
O : True if the file exists and is owned by the effective user ID.
G : True if the file exists and is owned by the effective group ID.
L : True if the file exists and is a symbolic link.
N : True if the file exists and has been modified since it was last read.
S : True if the file exists and is a socket.



4 | user input(read command)

Shell Scripting Tutorial


Hello Programmers, I’m Yash. Sole programmer at planetvearcity – a place where programmers come to learn, build, and grow.

Welcome to the tutorial series on shell scripting. In this video, we will cover the read command. To get input from the keyboard, we the read command. The read command takes input from the keyboard and assigns it to a variable.



3 | variables

Shell Scripting Tutorial


Hello Programmers, I’m Yash. Sole programmer at planetvearcity – a place where programmers come to learn, build, and grow.

Welcome to the tutorial series on shell scripting. In this video, we will cover variables.

The definition of a variables-a chunk of memory to which we can allocate values, interpret and manipulate its contents. Every programming language in existence has the concept of variables. There is no exception to the Bourne shell.

One thing to note is that when we declare variables along the way there should be no space around = sign. So let us get started.

The shell does not care about types of variables; they may store strings, integers, real numbers. Actually, these are all stored as strings.



2 | comments

Shell Scripting Tutorial


Hello Programmers, I’m Yash. Sole programmer at planetvearcity – a place where programmers come to learn, build, and grow.

Welcome to the tutorial series on shell scripting. In this video, we will cover comments and variables.

When writing Shell scripts, it is always a good practice to make your code clean and easily understandable. One of the ways to improve the readability of your code is by using comments. Adding comments to your scripts will make it easy for you to understand your code in the future. Let us go ahead and try using comments.

Comments are also useful when testing a script. Instead of deleting some lines, you can comment them out. If you are using a code editor like me then there is a shortcut to comment a given line or selected portion. In vs code its command plus forward slash.



1 | introduction

Shell Scripting Tutorial


Hello, I’m Yash. Sole programmer at planetvearcity – a place where programmers come to learn, build, and grow.

Welcome to the new tutorial series on shell scripting. In this video, we will be covering the introduction of shell scripting and write a hello world script.

Before we begin. I recommend you guys to watch my Linux command line tutorial. I have posted the link in the description. That tutorial is a prerequisite to this tutorial series. Moving along I will assume you understand basic Linux commands.

The shell script is a computer program designed to be run by the Unix/Linux.

There many different types of the shell such as:

  1. The Bourne Shell
  2. The C shell
  3. The Korne Shell
  4. The Bourne-Again shell


19 | sudo command

Linux Command Line Tutorial


  1. In this tutorial, we will learn how to use sudo command.
  2. The sudo command allows you to run programs as another user, by default the root user.
  3. Sudo is one of the commands you use very often if you spend a lot of time on the command line.
  4. Using sudo as root instead of login is better since you can give individual users restricted administrative rights without knowing the root password.