$ ./demo; echo $?
Testing traditional signals: wait for 14, ignore 12, catch 10:
  FAIL: 1 interrupt during wait
        [0] Interrupted system call; by caught signal 10
    ok: successfully waited for signal 14
    ok: caught signal 10 during wait, as expected
Testing realtime signals: wait for 36, ignore 35, catch 34:
  FAIL: 1 interrupt during wait
        [0] Interrupted system call; by caught signal 34
    ok: successfully waited for signal 36
    ok: caught signal 34 during wait, as expected
1
$ strace -o linux-6.8.trace ./demo; echo $?
Testing traditional signals: wait for 14, ignore 12, catch 10:
  FAIL: 2 interrupts during wait
        [0] Interrupted system call; by ignored signal
        [1] Interrupted system call; by caught signal 10
    ok: successfully waited for signal 14
    ok: caught signal 10 during wait, as expected
Testing realtime signals: wait for 36, ignore 35, catch 34:
  FAIL: 2 interrupts during wait
        [0] Interrupted system call; by ignored signal
        [1] Interrupted system call; by caught signal 34
    ok: successfully waited for signal 36
    ok: caught signal 34 during wait, as expected
1