diff --git a/unix/syscall_linux_test.go b/unix/syscall_linux_test.go
index cc3af9f6..7d9c8a16 100644
--- a/unix/syscall_linux_test.go
+++ b/unix/syscall_linux_test.go
@@ -239,13 +239,16 @@ func TestRlimitAs(t *testing.T) {
 
 func TestPselect(t *testing.T) {
 	for {
-		_, err := unix.Pselect(0, nil, nil, nil, &unix.Timespec{Sec: 0, Nsec: 0}, nil)
+		n, err := unix.Pselect(0, nil, nil, nil, &unix.Timespec{Sec: 0, Nsec: 0}, nil)
 		if err == unix.EINTR {
 			t.Logf("Pselect interrupted")
 			continue
 		} else if err != nil {
 			t.Fatalf("Pselect: %v", err)
 		}
+		if n != 0 {
+			t.Fatalf("Pselect: got %v ready file descriptors, expected 0", n)
+		}
 		break
 	}
 
@@ -254,7 +257,7 @@ func TestPselect(t *testing.T) {
 	var took time.Duration
 	for {
 		start := time.Now()
-		_, err := unix.Pselect(0, nil, nil, nil, &ts, nil)
+		n, err := unix.Pselect(0, nil, nil, nil, &ts, nil)
 		took = time.Since(start)
 		if err == unix.EINTR {
 			t.Logf("Pselect interrupted after %v", took)
@@ -262,6 +265,9 @@ func TestPselect(t *testing.T) {
 		} else if err != nil {
 			t.Fatalf("Pselect: %v", err)
 		}
+		if n != 0 {
+			t.Fatalf("Pselect: got %v ready file descriptors, expected 0", n)
+		}
 		break
 	}