getCurrentId

    fn getCurrentId() Id {
        switch (native_os) {
            .linux => {
                return LinuxThreadImpl.getCurrentId();
            },
            .driverkit, .ios, .maccatalyst, .macos, .tvos, .visionos, .watchos => {
                var thread_id: u64 = undefined;
                // Pass thread=null to get the current thread ID.
                assert(c.pthread_threadid_np(null, &thread_id) == 0);
                return thread_id;
            },
            .dragonfly => {
                return @as(u32, @bitCast(c.lwp_gettid()));
            },
            .netbsd => {
                return @as(u32, @bitCast(c._lwp_self()));
            },
            .freebsd => {
                return @as(u32, @bitCast(c.pthread_getthreadid_np()));
            },
            .openbsd => {
                return @as(u32, @bitCast(c.getthrid()));
            },
            .haiku => {
                return @as(u32, @bitCast(c.find_thread(null)));
            },
            .serenity => {
                return @as(u32, @bitCast(c.pthread_self()));
            },
            else => {
                return @intFromPtr(c.pthread_self());
            },
        }
    }