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C program to copy one string into another

Implementing strcpy() in C

In this program we are implementing our own strcpy() function, here we will learn how to copy one string to another without using library function?

In this program, we will read a string and copy the string into another using stringCopy() function which is implemented by own.

program to copy one string to another (implementation of strcpy) in C

#include <stdio.h>
 
/********************************************************
    *   function name       :stringCpy
    *   Parameter           :s1,s2 : string
    *   Description         : copies string s2 into s1
********************************************************/
void stringCpy(char* s1,char* s2);
 
int main()
{
    char str1[100],str2[100];
    
    printf("Enter string 1: "); 
    scanf("%[^\n]s",str1);//read string with spaces
    
    stringCpy(str2,str1);
    
    printf("String 1: %s \nString 2: %s\n",str1,str2);
    return 0;
}
 
/******** function definition *******/
void stringCpy(char* s1,char* s2)
{
    int i=0;
    while(s2[i]!='\0')
    {
        s1[i]=s2[i];
        i++;
    }
    s1[i]='\0'; /*string terminates by NULL*/
}

Output

Enter string 1:  Help in Programming
String 1:  Help in Programming
String 2:  Help in Programming

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