pm_api =
<
  pm_send_message (ulong, ulong, mparam, mparam) -> (ulong);
  pm_post_message (ulong, ulong, mparam, mparam) -> (ulong);
  ...

  mparam = ulong64 | int64+- | ptr -.x | pptr -.x;
  ...
>;

## pm api :: pm_api : {*}