C Language

C Intro

C Overview

C Tokens

C Constants

C Data types

C Operators

C Expressions

C I/O Operations

C Decision - Branching

C Decision - Looping

C Arrays

C String

C Functions

C Structure

C DMA

C Linked lists

C File Management

C Strings

Contents

• Initializing Strings
• Reading Strings from the terminal
• Writing strings to screen
• Arithmetic operations on characters
• String operations (string.h)
• String functions

String functions

• strlen()
• strcat()
• strcmp()
• strcmpi()
• strcpy()
• strlwr ()
• strrev()
• strupr()

Introduction

A string variable is any valid C variable name & is always declared as an array. The general form of declaration of a string variable is
Char string_name[size];
The size determines the number of characters in the string name.

Example: 
	char month[10]; 
	char address[100]; 
        

The size of the array should be one byte more than the actual space occupied by the string since the complier appends a null character at the end of the string.

Initializing Strings

/*String.c string variable*/ #include < stdio.h > main() { char month[15]; printf (“Enter the string”); gets (month); printf (“The string entered is %s”, month); }

Program description

In this example string is stored in the character variable month the string is displayed in the statement.
printf(“The string entered is %s”, month”); It is one dimension array. Each character occupies a byte. A null character (\0) that has the ASCII value 0 terminates the string.
The figure shows the storage of string January in the memory recall that \0 specifies a single character whose ASCII value is zero.
J A N U A R Y \0 Character string terminated by a null character ‘\0’.