What Is C? Features, Applications, Syntax And More

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C programming language continues to make a mark in the world of technology with its features and applications, suggesting that C will continue to remain relevant in the near future, too. Even with many high-level languages available today, people trying their hands at programming languages cannot neglect C programming language.

This article aims at solving your queries related to C programming language and takes you through the basics, starting with the history of C.

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C Programming Language: Brief History

Tracing back to the 1970s, Dennis Ritchie developed the procedural language in Bell laboratory to write a code for the Operating System in 1972, being the successor of B language by Ken Thompson. In the beginning, C was limited to UNIX OS, but later, due to its popularity stemming from its flexibility and simple usage, many compilers were released across cross-platforms, making it commercial. Today, C runs in many hardware platforms and OS platforms.

Also Read: Detailed History of C Language

ANSI gave C a commercial standard - American National Standard Institute in 1989. Thus, ANSI-C is the alternate name used for C. This programming language has been a base for C++, Java, modern programming languages, etc. It is, therefore, also known as the mother language or the base of many programming languages. C also supports many standard library functions for AI and ML.

Bonus fact: C language was developed to move code from assembly code to high-level language for the UNIX kernel code.

What is C?

Let's begin with the most common question. What is C? C is a popular programming language developed by Dennis M. Ritchie at AT&T Bell Laboratories. It can be used for debugging, testing, and maintaining processes as the program is compartmentalized into different modules. It is a mid-level language that displays the features of both a low-level and a high-level language.

All of this makes C a structured programming language. It is a prevalent general-purpose programming language with many data types, operators, control statements, 32 keywords, and built-in functions. The code, once written, can be made to run on any machine, making it a highly portable and compatible language.

Why is it important to learn C?

Knowledge of C language is fundamental in learning and developing skills in higher-level programming languages. C language plays a crucial role in the understanding of other programming languages. Many popular languages and C share some common concepts like data types, operators, and control statements, just to name a few.

Besides acting as a building block, knowledge of C language opens up avenues for career growth. Many entry-level positions are available that people equipped with C language can fill. The market offers job positions such as Junior Programmer, Senior Programmer, Quality Analyst, Software Developer, Game Programmer, and many more.

How does C work?

The program is compiled and converted into machine-readable object files. Refer to the following image for a better understanding:

C is also called a compiler language and can be used for compiler development or production. Let's have a look at some of the compilers that can be used to compile the source code and convert the source files.

Compilers for C

• Code blocks Dev-CPP
• Turbo C
• Clang compiler
• MinGW compiler, etc.

Bonus fact: C was adopted as a system development language because it produces code that runs almost as fast as the code written in assembly language.

Features of C

C language usually provides various features to programmers, making it easier to learn and write the program. Following are a few features that C offers.

1. Easy to learn

2. Robust structured language

3. Supports User-defined data types

4. Low-level access to memory

5. Base language

6. Many libraries

7. Fast speed

8. Memory Management, etc.

Bonus fact: These features help C to develop complex programs.

Applications of C

C language is used in a variety of applications:

1. Language compiler development
2. Network drivers
3. IoT
4. Embedded systems, systems application, etc.
5. Language interpreters
6. Modern programs
7. Financial application development, like trading apps

Syntax of C Language

The image above shows the structure of the C programming concepts, where the curly brackets {} constitute the body. The entire code is written by following this structure. The following is a program written in syntax of C language:

#include<stdio.h>

int main()

{

#write a program to add two numbers
int a = 4, b=5;

float d = 4, e=5;

int c,m;

float f;

c = a + b;
f = d + e;

printf{"Get the user input \n"};

scanf{"%d",m};

printf{"Display the information \n"};

printf{"%d",c};

printf{"%d",f};

return 0;

}

Here are the details:

1. # include<stdio.h>

This is the header source file, which contains the functions for C. stdio - standard input-output.

2. int main()

Declaration of the main method.

3. { }

Code should be written within these curly braces.

4. #

This is used if the developer needs to comment on that line.

5. int, float

These are the data types that will inform the computer about its state. For example, to make a computer add two integer numbers, we have to include int - means integer, and their size is 2 or 4 byte. We include the data type float for decimal numbers, which are 4 bytes.

6. scanf()

This common function is used to get the user's input or value. For example, to log in to Gmail, the computer gets some input in the form of our email address and password. The same thing applies here.

It also has a simple syntax: int scanf(const char *format, ...);

7. printf()

This output function is used to display the information in the console.

Basic syntax of printf function : printf("format string", arguments);

8. ;

You would have noticed this ";" at every end of the code line. Using this, we tell the computer that the line ends here or goes to a new line.

9. \n

This is used for the newline denotation.

10. return 0

This return statement is used to return the value. Usually, we use return 0 when main method declaration is int main() or else for void main() as main method declaration we do not use return type as void won't return. If it sounds confusing, don't take it seriously, haha.

Real-world examples of C

C language seeps into the day-to-day things we see or work with. Here are some real-world scenarios where you can spot the application of C language.

GUI -Graphical User Interface

C language is used in the design work for Adobe Photoshop, Adobe Image Ready and as runtime OS for Windows 32.

3-D movies

C is fast and efficient, and they have the capacity to handle large amounts of data and do loads of calculations. Due to their efficiency and time-saving ability, the language is used in the creation of applications that are used for 3-D movies.

Operating Systems design

UNIX, developed in Bell Labs, was written in C language. C language has a major role in developing OS like Linux, Kernels of Mac, Android, IOS, and Microsoft Windows.

Embedded Systems

An embedded system can be seen as a combination of computer hardware and software designed to carry out a specific function. Embedded systems may also function within larger systems. The systems can be programmable or have a fixed functionality. Industrial machines, consumer electronics, automobiles, agricultural and processing industry devices, medical equipment, cameras, digital watches, household appliances, airplanes, vending machines and toys, and mobile devices are possible locations for an embedded system.

Browser design

Web browsers like Mozilla Firefox, Google file system, Thunderbird, etc., are written in C.

Bonus fact: Do you love playing chess, tic-tac-toe, snake game? These interesting games are also written in C language.

FAQs

Q1. How did C become a popular language?

C became popular because of its portability, efficiency, simplicity, libraries, influence on other languages, historical significance (linked to UNIX), openness, flexibility, legacy codebase, and educational value.

Q2. Why is C a procedural programming language?

A particular kind of computer programming language called procedural programming language adheres to a set of instructions in order to accomplish a job or program. Because it is an imperative procedural language that enables structured programming, lexical variable scope, and recursion together with a static variable type system, C is referred to as a procedural programming language.
Any particular procedure may be called at any time throughout the execution of a program, either by other processes or that procedure itself.

Q3. What is the use of the built-in function printf function in C?

To print output on the screen in C, we use the printf function. It is a part of the C standard library "stdio.h" and can allow formatting the output in numerous ways.
The correct syntax of printf is as follows: printf("format String", Arguments); Here, the format string is a string that specifies the output, and it may also contain a format specifier to print the value of any variable such as character and an integer value.

Q4. What is meant by a void keyword?

The void keyword in C indicates the absence of a value. It is a data type with no value or memory allocation.

Q5. What is dynamic allocation in C?

Dynamic allocation in C refers to the process of allocating memory during the execution of a program. In C programming, there are four functions for dynamic memory allocation: malloc(), calloc(), realloc(), and free(). Dynamic allocation is used when the size of the data is not known at compile time, or when the size of the data may change during program execution.

Q6. Define double pointer.

A double pointer in C is a pointer that points to another pointer. It is also known as a pointer-to-pointer. In C, a variable that stores the memory address of another variable or data type is known as a pointer. When we need to save the address of another pointer, we use a double pointer.The address of the variable is stored in the first pointer, while the address of the first pointer is stored in the second pointer.

Q7. What is callee function in C?

In C, the term "callee function" refers to a function that another function calls or invokes. It's the function that performs a specific task when it's called by the calling function (also known as the "caller function"). The callee function typically receives parameters (arguments) from the caller function, processes them, and may return type a value to the caller function. In simpler terms, the callee function is what you call when you want a particular operation to be performed within your program.

Q8. Mention some higher-level languages.

Some higher-level languages are:

1. Python
2. Java
3. JavaScript
4. C++
5. Ruby
6. Perl
7. PHP

Q9. Define memory leak.

When a program wrongly handles the allocation of memory in such a manner that memory that is no longer required is not released, it results in a resource leak known as a memory leak in C. This can happen if a program forgets to deallocate the allocated memory or loses track of the allocated memory. The program will gradually use more memory, which might eventually result in memory issues or serious system failures.

Q10. What is a recursive function?

A function that calls itself directly or indirectly to solve a problem by dividing it into smaller, simpler versions of the same problem is known as a recursive function in the C programming language. The recursive function process continues until a base case is reached, which is a condition that stops the recursion. Recursive functions are helpful in solving issues that may be divided into smaller sub-problems, such as sorting algorithms, tree traversals, and mathematical difficulties like computing a number's factorial or creating the Fibonacci sequence.

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