message: update kqueue helper
diff: #include <stdint.h>
  +#define EVFILT_READ (-1)
  +#define EVFILT_WRITE (-2)
  +
  /* kevent system call flags */
  #define KEVENT_FLAG_NONE 0x000000 /* no flag value */
  #define KEVENT_FLAG_IMMEDIATE 0x000001 /* immediate timeout */
  