How to write c code in linux how to#
How to write c code in linux series#

The variable counter is initialized to 1. The while loop below lists all the numbers from 1 to 10 when executed. This is one of the easiest loops to work with. In this section, we shall have a peek at some of the loops which you’d also find in other programming languages. This comes in handy in performing repetitive tasks.

How to write c code in linux series#

If statement with OR logic Use Looping Constructsīash loops allow users to perform a series of tasks until a certain result is achieved. When using the OR logic, that is represented by || symbol, either one of the conditions needs to be satisfied with the script to give the expected results. The & operator is used to denote the AND logic. You can use the if statement alongside the AND logic operator to execute a task if two conditions are satisfied.

if condition1įor example, we have a script for a lottery that checks if the number entered is either 90, 60 or 30. This statement takes the following format. In scenarios where there are multiple conditions and different outcomes, the if-elif-else statement is used. If-else statement in Shell Script Example of an if-elif-else Statement However, if the score falls below 70, the output ‘ You failed’ will be printed. If the score is greater than or equal to 70, you get a ‘ Great job, You passed!’ message. The script below reads the input score and checks whether it is greater than or equal to 70. If Statement in Shell Script Example of an if-else Statementįor situations where you have 2 possible outcomes: – whether this or that – the if-else statement comes in handy. Other comparison operators you can use include:įor example, the if-statement block below prints out ‘ Work Harder’ if the input score is any value less than 50. The comparison operator = is used to test if the score entered, which is stored in the variable x, is equivalent to 100. If the score corresponds to 70, the script returns the output “ Good job!”. The above shell script prompts the user to provide a score that is then stored in a variable x. Let’s take a look at the shell script below. We will start off with the fundamental use of the if statement to test a single condition. The if statement can be used to test single or multiple conditions. We are going to cover the if, if-else, and elif conditional statements. Like other programming languages, conditional statements are used in bash scripting to make decisions, with only a slight variation in the syntax. Using Conditional Statements to Execute Code $ chmod +x hello.shįinally, run the shell script using either of the commands: $ bash hello.shĬreate Hello World Shell Script 2. The next step is to make the script executable by assigning execute permission using the chmod command as shown. The last line is the command that prints the ‘ Hello World’ message on the terminal.Comments are always preceded by the hash sign #. A comment is a statement that describes what a shell script does and is not executed when the script is run. There are other scripting languages such as Python which is denoted by #!/usr/bin/python3 and Perl whose shebang header is is denoted by #!/usr/bin/perl. In this case, this will be the bash shell indicated by /bin/bash. This is a special construct that indicates what program will be used to interpret the script. The first line – #!/bin/bash – is known as the shebang header.You can either execute the a.out to see the output (or) rename it to some other meaningful name and execute it as shown below.Let’s go over the shell script line by line. Ii g++-4.3 4.3.3-5ubuntu4 The GNU C++ compilerĬompile the using c++ command as shown below. Ii g++ 4:4.3.3-1ubuntu1 The GNU C++ compiler Make sure g++ is installed on your system as shown below.Ĭ++: /usr/bin/c++ /usr/include/c++ /usr/share/man/man1/c++.1.gz Make sure C++ Compile (g++) is installed on your system

How to write c code in linux how to#

In this article, let us review very quickly how to write a basic Hello World C++ program and how to compile *.cc program on Linux or Unix OS.Ĭreate the program using a Vim editor as shown below. Can you explain it with a simple example?Īnswer: Last week we reviewed how to write C program on Unix OS. Question: I would like to understand the basics of how to write, compile and execute a C++ program on Linux OS.