Learn the basics of C, a widely used programming language
C is one of the most popular programming languages and is widely used in computer science courses around the world. It is also commonly learned alongside Python and Java in schools. While C is not the easiest language to learn, it is a fundamental language that provides a deep understanding of programming principles.
Today, C is heavily used in embedded devices and powers many Internet servers running on Linux. The Linux kernel itself is built using C, making it a critical part of the infrastructure for Android devices. With C, you have the power to create software that runs on a global scale.
When C was created, it was considered a high-level language because it was portable across different computer architectures. Unlike languages such as Python, Ruby, or JavaScript, C is a compiled language, meaning it generates a binary file that can be directly executed and distributed. One of the unique aspects of C is its ability to manually manage memory, making it ideal for writing programs for devices like Arduino.
Let’s dive into a basic C program called “Hello, World!”
#include <stdio.h>
int main(void) {
printf("Hello, World!");
}
In this program, we first import the stdio
library, which provides input/output functions. C is a small language, and anything beyond its core functionality is provided by libraries. The stdio
library, for example, provides the printf()
function.
In C, code is organized into functions. Every C program has a main()
function, which serves as the entry point for the program. Functions in C can have arguments and return a value. In the case of main()
, it doesn’t accept any arguments and returns an integer value (int
).
The printf()
function is an example of a function invocation. Inside the stdio
library, printf()
is defined as int printf(const char *format, ...);
. Here, we pass a string wrapped in double quotes as an argument to the function.
To compile and run a C program, you need a C compiler. Most Linux and macOS systems come with a C compiler pre-installed. For Windows, you can use the Windows Subsystem for Linux (WSL) to get a C compiler.
To compile the hello.c
program, run the following command in your terminal:
gcc hello.c -o hello
This will generate an executable file named hello
. To run the program, type:
./hello
And you should see the output: “Hello, World!”
C programs are highly optimized and result in small executable files. This optimization makes C ideal for embedded devices with limited resources.
Explore more C tutorials:
- Variables and types
- Constants
- Operators
- Conditionals
- Loops
- Pointers
- Functions
- Arrays
- Strings
- Input/output
- Type definitions
- Enumerated types
- Structs
- Header files
- The C preprocessor
Tags: C programming, embedded devices, Linux, compiled language, memory management