The C library function char *strcat(char *dest, const char *src) appends the string pointed to by src to the end of the string pointed to by dest.
An array of characters is called a string.
Declaration
Following is the declaration for an array −
char stringname [size];
For example − char string[50]; string of length 50 characters
Initialization
- Using single character constant −
char string[10] = { ‘H’, ‘e’, ‘l’, ‘l’, ‘o’ ,‘\0’}- Using string constants −
char string[10] = "Hello":;
Accessing − There is a control string "%s" used for accessing the string till it encounters ‘\0’.
The strcat( ) function
This is used for combining or concatenating two strings.
The length of the destination string must be greater than the source string.
The result concatenated string is the source string.
Syntax
The syntax is as follows −
strcat (Destination String, Source string);
Example Program
The following program shows the usage of strcat() function.
#include <string.h>
main(){
char a[50] = "Hello \n";
char b[20] = "Good Morning \n";
strcat (a,b);
printf("concatenated string = %s", a);
}Output
When the above program is executed, it produces the following result −
Concatenated string = Hello Good Morning
Example
Let’s see another example.
Following is the C program to concatenate source string to destination string using strcat library function −
#include<stdio.h>
#include<string.h>
void main(){
//Declaring source and destination strings//
char source[45],destination[50];
//Reading source string and destination string from user//
printf("Enter the source string : \n");
gets(source);
printf("Enter the destination string : \n");
gets(destination);
//Concatenate all the above results//
strcat(source,destination);
//Printing destination string//
printf("The modified destination string :");
puts(source);
}Output
When the above program is executed, it produces the following result −
Enter the source string :Tutorials Point Enter the destination string :C programming The modified destination string :Tutorials Point C programming