There is a command group 'az_iot_device_c2d message'. This group of commands could 'cloud to device messaging commands'. The group of commands has global parameter '--debug' which means 'Increase logging verbosity to show all debug logs.'. The group of commands has global parameter '--help -h' which means 'Show this help message and exit.'. The group of commands has global parameter '--only-show-errors' which means 'Only show errors, suppressing warnings.'. The group of commands has global parameter '--output -o' which means 'Output format.'. The group of commands has global parameter '--query' which means 'JMESPath query string. See <a href="http://jmespath.org/">http://jmespath.org/</a> for more information and examples.'. The group of commands has global parameter '--subscription' which means 'Name or ID of subscription. You can configure the default subscription using `az account set -s NAME_OR_ID`.'. The group of commands has global parameter '--verbose' which means 'Increase logging verbosity. Use --debug for full debug logs.'. This group contains a child command 'az_iot_device_c2d message_receive'.The syntax is: az iot device c2d-message receive --device-id
                                  [--abandon {false, true}]
                                  [--complete {false, true}]
                                  [--hub-name]
                                  [--lock-timeout]
                                  [--login]
                                  [--reject {false, true}]
                                  [--resource-group]. The 1th example of the child command would be to use it to 'basic usage', the syntax is: az iot device c2d-message receive -d {device_id} -n {hub_name} -g {resource_group}. The 2th example of the child command would be to use it to 'receive a message and set a lock timeout of 30 seconds for that message', the syntax is: az iot device c2d-message receive -d {device_id} -n {hub_name} -g {resource_group} --lt {30}. The 3th example of the child command would be to use it to 'receive a message and ack it as  complete  after it is received', the syntax is: az iot device c2d-message receive -d {device_id} -n {hub_name} -g {resource_group} --complete. The 4th example of the child command would be to use it to 'receive a message and reject it after it is received', the syntax is: az iot device c2d-message receive -d {device_id} -n {hub_name} -g {resource_group} --reject. The parameter '--device-id -d' is required. It is used to target device id.. The parameter '--abandon' is optional. abandon the cloud-to-device message after receipt.. The parameter '--complete' is optional. complete the cloud-to-device message after receipt.. The parameter '--hub-name -n' is optional. iot hub name or hostname. required if --login is not provided.. The parameter '--lock-timeout --lt' is optional. specifies the amount of time a message will be invisible to other receive calls.. The parameter '--login -l' is optional. this command supports an entity connection string with rights to perform action. use to avoid session login via "az login". if both an entity connection string and name are provided the connection string takes priority. required if --hub-name is not provided.. The parameter '--reject' is optional. reject the cloud-to-device message after receipt.. The parameter '--resource-group -g' is optional. name of resource group. you can configure the default group using `az configure --defaults group=<name>`.. 