Invoke a callback

A callback function (or just callback) is a function that you write to handle a particular event.

The DataBlade® API provides the following functions to handle invocation of a callback function.
Callback task DataBlade API function
Register a callback mi_register_callback(), mi_unregister_callback()
Enable a callback mi_enable_callback()
Disable a callback mi_disable_callback()
Retrieve a pointer to the callback function mi_retrieve_callback()
For the DataBlade API to invoke a callback when the associated event occurs, the following conditions must be met in the DataBlade API module:
  • The module must register the callback for the event on the current connection.

    The mi_register_callback() function registers a callback for a particular event. The DataBlade API module that requires the event handling must register the callback.

  • The registered callback must be enabled.

    It is possible to disable a registered callback to suspend its invocation. The mi_enable_callback() function enables a previously disabled callback.

In addition, a module can save a registered callback and restore it at a later time.