# ISessionListener ## **Overview** **Related Modules:** [Softbus](Softbus.md) **Description:** Defines session callbacks. When a session is opened or closed, or there is data to process, the related callback is invoked. **Since:** 1.0 **Version:** 1.0 ## **Summary** ## Data Fields

Variable Name

Description

onSessionOpened )(int sessionId)

int(* 

Called when a session is opened.

onSessionClosed )(int sessionId)

void(* 

Called when a session is closed.

onBytesReceived )(int sessionId, const void *data, unsigned int dataLen)

void(* 

Called when data is received.