Use assert_eq(0) for epoll_ctl

Author: tiif

tests/pass-dep/libc/libc-epoll.rs

@@ -546,10 +546,10 @@ fn test_epoll_lost_events() {
     // Register both fd to the same epoll instance.
     let mut ev = libc::epoll_event { events: EPOLL_IN_OUT_ET, u64: fds[0] as u64 };
     let res = unsafe { libc::epoll_ctl(epfd, libc::EPOLL_CTL_ADD, fds[0], &mut ev) };
-    assert_ne!(res, -1);
+    assert_eq!(res, 0);
     let mut ev = libc::epoll_event { events: EPOLL_IN_OUT_ET, u64: fds[1] as u64 };
     let res = unsafe { libc::epoll_ctl(epfd, libc::EPOLL_CTL_ADD, fds[1], &mut ev) };
-    assert_ne!(res, -1);
+    assert_eq!(res, 0);
 
     //Two notification should be received. But we only provide buffer for one event.
     let expected_event0 = u32::try_from(libc::EPOLLOUT).unwrap();
@@ -578,10 +578,10 @@ fn test_ready_list_fetching_logic() {
     // Register both fd to the same epoll instance. At this point, both of them are on the ready list.
     let mut ev = libc::epoll_event { events: EPOLL_IN_OUT_ET, u64: fd0 as u64 };
     let res = unsafe { libc::epoll_ctl(epfd, libc::EPOLL_CTL_ADD, fd0, &mut ev) };
-    assert_ne!(res, -1);
+    assert_eq!(res, 0);
     let mut ev = libc::epoll_event { events: EPOLL_IN_OUT_ET, u64: fd1 as u64 };
     let res = unsafe { libc::epoll_ctl(epfd, libc::EPOLL_CTL_ADD, fd1, &mut ev) };
-    assert_ne!(res, -1);
+    assert_eq!(res, 0);
 
     // Close fd0 so the first entry in the ready list will be empty.
     let res = unsafe { libc::close(fd0) };