chore: remove unused for loop in test

unix/syscall_linux_test.go

@@ -460,22 +460,6 @@ func TestPselectWithSigmask(t *testing.T) {
 		}
 		break
 	}
-
-	for {
-		var sigmask unix.Sigset_t
-		sigmask.Val[0] |= 1 << (uint(unix.SIGUSR1) - 1)
-		n, err := unix.Pselect(0, nil, nil, nil, &unix.Timespec{Sec: 0, Nsec: 0}, &sigmask)
-		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
-	}
 }
 
 func TestSchedSetaffinity(t *testing.T) {