getParkTid

fn getParkTid() ParkTid {
    switch (native_os) {
        .haiku => {
            if (park_sem == -1) {
                park_sem = std.c._kern_create_sem(0, null);
                if (park_sem < 0) @panic("_kern_create_sem failed");
                _ = std.c.on_exit_thread(destroyParkSem, null);
            }
            return park_sem;
        },
        else => {
            return if (Thread.current) |thread| thread.id else std.Thread.getCurrentId();
        },
    }
}