# MBCommPStateCallback

## Definition

  `#include <nitro/mb.h>`
  `typedef void (*MBCommPStateCallback)(u16 child_aid, u32 status, void* arg);`

## Description

Defines the format of the callback function, which is called every time the parent state changes. The arguments are described below:

Arguments | Description
child_aid | When a callback is a notification for one specific child, shows the aid of that child. You can get details for a specific child by calling the `MB_CommGetChildUser` function and specifying this value.
status | Indicates one of the states shown by `MBCommPState`.
arg | The variable corresponding to the state to be notified is passed. For details on each state, see the description of `MBCommPState`.

## See Also

`MBCommPState
MB_CommGetChildUser
MB_CommSetParentStateCallback
MB_CommGetParentState`

## Revision History

2004/09/10 Added description regarding the expansion of the argument `arg`.
2004/08/09 Initial version.

CONFIDENTIAL