xref: /xnu-11215/tests/dev_zero.c (revision 1031c584)
1 #include <stdio.h>
2 #include <fcntl.h>
3 #include <util.h>
4 #include <unistd.h>
5 #include <darwintest.h>
6 
7 T_DECL(dev_zero,
8     "test reading from /dev/zero",
9     T_META_ASROOT(false))
10 {
11 	int dev = opendev("/dev/zero", O_RDONLY, 0, NULL);
12 	char buffer[100];
13 
14 	for (int i = 0; i < 100; i++) {
15 		buffer[i] = 0xff;
16 	}
17 
18 	int rd_sz = read(dev, buffer, sizeof(buffer));
19 
20 	T_EXPECT_EQ(rd_sz, 100, "read from /dev/zero failed");
21 
22 	for (int i = 0; i < 100; i++) {
23 		if (buffer[i]) {
24 			T_FAIL("Unexpected non-zero character read from /dev/zero");
25 		}
26 	}
27 
28 	close(dev);
29 }
30