Implement strcpy function

Hi,
I want to implement strcpy function, but something is go wrong.
I have made debug and the code works until execute the function.
I receive an error something with segmentation fault.
Thank you.

#include <stdio.h>
#include <stdlib.h>

char *strcpy(char *destination, char *source)
{

char *saved = destination;
while(*source != '\0')
{

*destination = *source;
destination++;
source++;​

}
return saved;​

}

int main()
{

char *ptr1 = "kjshdfoiswledkj";
char *ptr2 = NULL;
printf("\n The value of ptr1 is : %s\n", ptr1);
printf("\n The value of ptr2 is : %s\n", ptr2);
strcpy(ptr2, ptr1);
printf("\n The value of ptr1 is : %s\n", ptr1);
printf("\n The value of ptr2 is : %s\n", ptr2);
return 0;​

}