6 int main(int argc, char** argv)
13 memset(zeros, 0, sizeof zeros);
14 memset(ones, 1, sizeof ones);
17 fd = open("test1.data", O_RDWR|O_CREAT, 0666);
19 err(1, "creating file");
20 if (write(fd, zeros, sizeof zeros) < 0)
21 err(1, "writing zeros");
25 fd = open("test1.data", O_RDWR);
27 err(1, "opening file");
28 if (lseek(fd, 600, SEEK_SET) < 0)
31 if (write(fd, ones, sizeof ones) < 0)
32 err(1, "writing ones");
36 addr = mmap(0, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
37 if (addr == MAP_FAILED)
39 unlink("test1.scratch");
40 fd2 = open("test1.scratch", O_RDWR|O_CREAT, 0666);
42 err(1, "creating scratch");
44 if (write(fd2, addr, 4096) < 0)
45 err(1, "writing scratch");