|  | Paho Asynchronous MQTT C Client Library
    | 
#include <MQTTAsync.h>
Structure to define call options. For MQTT 5.0 there is input data as well as that describing the response method. So there is now also a synonym MQTTAsync_callOptions to better reflect the use. This responseOptions name is kept for backward compatibility.
| char struct_id[4] | 
The eyecatcher for this structure. Must be MQTR
| int struct_version | 
The version number of this structure. Must be 0 or 1 if 0, no MQTTV5 options
| MQTTAsync_onSuccess* onSuccess | 
A pointer to a callback function to be called if the API call successfully completes. Can be set to NULL, in which case no indication of successful completion will be received.
| MQTTAsync_onFailure* onFailure | 
A pointer to a callback function to be called if the API call fails. Can be set to NULL, in which case no indication of unsuccessful completion will be received.
| void* context | 
A pointer to any application-specific context. The the context pointer is passed to success or failure callback functions to provide access to the context information in the callback.
| MQTTAsync_token token | 
A token is returned from the call. It can be used to track the state of this request, both in the callbacks and in future calls such as MQTTAsync_waitForCompletion.
| MQTTAsync_onSuccess5* onSuccess5 | 
A pointer to a callback function to be called if the API call successfully completes. Can be set to NULL, in which case no indication of successful completion will be received.
| MQTTAsync_onFailure5* onFailure5 | 
A pointer to a callback function to be called if the API call successfully completes. Can be set to NULL, in which case no indication of successful completion will be received.
| MQTTProperties properties | 
MQTT V5 input properties
| MQTTSubscribe_options subscribeOptions | 
| int subscribeOptionsCount | 
| MQTTSubscribe_options* subscribeOptionsList | 
 1.8.17
 1.8.17