#include <unistd.h>
#include <stdio.h>

char filename[] = "file20M";

int main(void){
   int fd;
   if((fd = creat(filename, 0600)) == -1){
		fprintf(stderr, "creating failed: returnvalue is %d\n", fd);
		exit(1);
   }
	if(write(fd, "A", 1) != 1)
		fprintf(stderr, "write A failed\n");
	if(lseek(fd, 20000000, SEEK_SET) != 20000000)
		fprintf(stderr,"lseek failed\n");
	if(write(fd, "B", 1) != 1)
		fprintf(stderr, "write B failed\n");
	printf("created file with a hole in it\n");
   exit(0);
}