#include<stdio.h>

int main()
{
	FILE *f;
	char hello[13] = "Hello World!";
	char string[13];

	f = fopen("test.txt", "w+");
	fwrite(hello, 1, 12, f);
	fseek(f, 6, SEEK_SET);
	fread(string, 1, 5, f);
	string[5]=0;
	printf("%s\n", string);
	fclose(f);
}