How parameters and replies are managed in API v4
================================================

Applicative bindings receive and emit massages carrying data.
These data are called parameters of the message. This paper
presents how parameters are handled in the API of bindings
version 4.

Emitting parameters
-------------------

Let start with the simplest. Emitting parameters is done
in the following situations:

- broadcasting or pushing events
- calling or sub-calling a verb

The procedure to follow is:

- collect or build the data that will be emitted,
- if needed, add one reference to each data that remains
  used after emission,
- emit the data using an array.

The sent parameters are released by the binder framework
when the sending is completed.

Here is an example:

```C
int push(afb_event_t event, int value)
{
	afb_data_t params[1] = { NULL };
	afb_evt_new_data(event, &params[0]);
	afb_data_copy(params[0], AFB_TYPE_INT, &value, sizeof value);
	afb_event_push(event, 1, params);
}

```