1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
|
#include <stdio.h>
#include <errno.h>
#include <unistd.h>
#include <fcntl.h>
int main() {
int f, f2, f3;
printf("DUP\n");
f = open("/", O_RDONLY);
f2 = open("/", O_RDONLY);
f3 = dup(f);
printf("errno: %d\n", errno);
printf("f: %d\n", f != f2 && f != f3);
printf("f2,f3: %d\n", f2 != f3);
printf("close(f1): %d\n", close(f));
printf("close(f2): %d\n", close(f2));
printf("close(f3): %d\n", close(f3));
printf("\n");
errno = 0;
printf("DUP2\n");
f = open("/", O_RDONLY);
f2 = open("/", O_RDONLY);
f3 = dup2(f, f2);
printf("errno: %d\n", errno);
printf("f: %d\n", f != f2 && f != f3);
printf("f2,f3: %d\n", f2 == f3);
printf("close(f1): %d\n", close(f));
printf("close(f2): %d\n", close(f2));
printf("close(f3): %d\n", close(f3));
printf("\n");
errno = 0;
return 0;
}
|
