How to set file pointer offset in C language

/*
Example: set pointer to an offset in C language
*/

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

int main(int argc, char const *argv[])
{
    char *ptr0 = "Hello lautturi world";
    char *ptr1 = ptr0+6; // set ptr1 = ptr0 +6
    printf("ptr0: %s\n", ptr0); // output: Hello lautturi world
    printf("ptr1: %s", ptr1);   // output: lautturi world
    return 0;
}