Learning C language Tutorial for Beginners in PDF

It is a free, unofficial book about the C programming language that was made to help people learn. All of the information comes from the Stack Overflow Documentation, written by many hardworking people at Stack Overflow. It has nothing to do with either Stack Overflow or the C language.

The content is licensed under Creative Commons BY-SA, and the contributors to each chapter are listed in the "Credits" section at the end of this book. Unless otherwise stated, images are the property of their respective owners. All trademarks and registered trademarks belong to the companies that made them.

An overview of Learning C language

C is a general-purpose, imperative computer programming language that supports structured programming, lexical variable scope, and recursion. A static type system keeps many unintended operations from happening. By design, C has structures that map well to typical machine instructions. Because of this, it has been used for a long time in applications that used to be coded in assembly language, such as operating systems and software for computers ranging from supercomputers to embedded systems.

Even though the language is low-level, it was made to encourage platform programming. A C program written to meet standards and be portable can be run on a wide range of computer platforms and operating systems with only minor changes to the source code. The language can now be used on various platforms, from microcontrollers built into devices to supercomputers.

Dennis Ritchie created C at Bell Labs between 1969 and 1973. It was used to rewrite the Unix operating system. Since then, it has grown to be among the most used programming languages. Most computer architectures and operating systems can use C compilers from different companies.

Compilers and operating systems have different ways of putting together a C program. Most operating systems don't have a compiler, so you'll need to add one. Some choices that compilers often make are:

• GNU Compiler Collection (GCC)
• MSVC, Microsoft Visual C/C++ build tools; a front-end for the C language family

The following documents should give you a good overview of how to start using a few of the most common compilers:

• Getting Started with Microsoft Visual C
• Getting Started with GCC
• Support for the compiler's C version

Compilers support standard C in different ways, and many still require C99. For example, as of the 2015 release, MSVC supports most of C99, but there are still some important exceptions for support of the language itself (for example, the preprocessing seems nonconformant) and for the C library (for example), and they don't always document their "implementation-dependent choices." Wikipedia has a table that shows which popular compilers offer support.

Some compilers, like GCC, have offered or still offer compiler extensions that add extra features that the compiler makers think are important, useful, or might be added to a future version of C, but are not part of any C standard at the moment. Since these extensions are compiler-specific, you can consider them incompatible with other compilers. Compiler developers may remove or change them in later versions of the compiler.

Most of the time, compiler flags can be used to control how these extensions are used.
Also, many developers use compilers that only support specific versions of C because that's what the environment or platform they're building for requires.
When choosing a compiler, it is best to pick one that works best with the latest version of C that can be used in the target environment.

Since white space doesn't matter in C (it doesn't change how the code works), programmers often use it to make the code easier to read and understand. This is called the "code style." It is a set of rules and instructions that are used to write the source code. It talks about things like how to indent lines, whether to use spaces or tabs, where to put braces, how to use spaces around operators and brackets, how to name variables, and so on.

Code style is separate from the standard, and it's mostly a matter of opinion (different people find different styles easier to read), so it's usually not a good idea to talk about it on SO. Consistency is the most important thing to remember regarding style in your code. Choose or make a style and stick to it. Many named styles are commonly used, and programmers often choose one instead of making their own.

Some common indentation styles are K&R, Allman, GNU, etc. Some of these styles come in more than one form. For example, Allman can be used as either the regular Allman or the popular Allman-8. You can find some of the most popular styles on Wikipedia. These style names come from the standards that authors or organizations publish so that the many people who contribute to their code can use them. For example, the GNU formatting guide is part of the GNU coding standards document, so everyone can easily read the code if they know the style.