Book Image

Learn C Programming

By : Jeff Szuhay
Book Image

Learn C Programming

By: Jeff Szuhay

Overview of this book

C is a powerful general-purpose programming language that is excellent for beginners to learn. This book will introduce you to computer programming and software development using C. If you're an experienced developer, this book will help you to become familiar with the C programming language. This C programming book takes you through basic programming concepts and shows you how to implement them in C. Throughout the book, you'll create and run programs that make use of one or more C concepts, such as program structure with functions, data types, and conditional statements. You'll also see how to use looping and iteration, arrays, pointers, and strings. As you make progress, you'll cover code documentation, testing and validation methods, basic input/output, and how to write complete programs in C. By the end of the book, you'll have developed basic programming skills in C, that you can apply to other programming languages and will develop a solid foundation for you to advance as a programmer.
Table of Contents (33 chapters)
Section 1: C Fundamentals
Section 2: Complex Data Types
Section 3: Memory Manipulation
Section 4: Input and Output
Section 5: Building Blocks for Larger Programs

Converting strings into numbers with atoi() and atod()

Another way to convert strings into values is to use the conversion functions declared in stdlib.h—ASCII to integer (atoi()) and ASCII to float (atof()). These functions take a string buffer as their function parameter and return a value of the relevant type. atoi() returns an int value while atof() returns a double value. These functions are based on more general strings to the <type> functions—strtol(), strtoll(), strtod(), strtof(), and strtold(), where l is a long integer value, ll is a long long integer value, d is double, f is a float value, and ld is a long double value.

The ato<type>() functions assume a single value is given in the input array. The strto<type>() functions have additional parameters that allow them to convert either the whole string or a smaller part of a larger string.

We don't always need the specificity or flexibility that the strto<type&gt...