broadcast.md

# Broadcast
## **Overview**
Provides data subscription and data push for services.
With this module, the [Service](service.md), [Feature](feature.md), or other modules can broadcast events or data. All services that listen to these events or data can receive these broadcasts.
**Since:**
1.0
**Version:**
1.0
## **Summary**
## Data Structures

Data Structure Name	Description
Consumer	Defines the topic consumer used to receive events and push data. You need to implement this struct for your application.
Provider	Defines the provider of events and data of a topic.
Subscriber	Defines the subscriber for external interfaces to subsribe to events and data of a topic.

## Typedefs

Typedef Name	Description
Topic	typedef uint32 Indicates the topic of an event or data, which is used to distinguish different types of events or data.

## Enumerations

Enumeration Name	Description
BroadcastErrCode { EC_ALREADY_SUBSCRIBED = EC_SUCCESS + 1 }	Enumerates error codes unique to the Broadcast service.

## **Details**
## **Typedef Documentation**
## Topic
```
typedef uint32 [Topic](broadcast.md#gaf03f5bc94cad32ab628a6cdee09b0542)
```
**Description:**
Indicates the topic of an event or data, which is used to distinguish different types of events or data.
## **Enumeration Type Documentation**
## BroadcastErrCode
```
enum [BroadcastErrCode](broadcast.md#ga98f7a28020aa045ad049d116e1ca666d)
```
**Description:**
Enumerates error codes unique to the Broadcast service.

Enumerator	Description
EC_ALREADY_SUBSCRIBED	Error code showing that a topic has been subscribed to