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fredlcore / BSB-LAN

LAN/WiFi interface for Boiler-System-Bus (BSB) and Local Process Bus (LPB) and Punkt-zu-Punkt Schnittstelle (PPS) with a Siemens® controller used by Elco®, Brötje® and similar heating systems
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[QUESTION] Publish MQTT into BSB_LAN_custom_setup.h file #603

Closed Turbox35 closed 7 months ago

Turbox35 commented 7 months ago

Hello,

This is not a bug or request, the problem is on my side. I would like to publish MQTT message at the end of the setup (run one time at the end of the boot) and I use the command: MQTTPubSubClient->publish(Topic.c_str(), output, n, true); But it fails. BSB-LAN-master\BSB_LAN\BSB_LAN_custom_setup.h:50:66: error: no matching function for call to 'PubSubClient::publish(const char*, String&, size_t&, bool)' Is it due to the MQTT client which is not already declared? Or I miss something?

Many thanks.

fredlcore commented 7 months ago

Well, the error message is clear: You are calling a function that expects other parameters than you are sending. If you look at PubSubClient.h, you'll see that there are four different ways to call "publish":

   boolean publish(const char* topic, const char* payload);
   boolean publish(const char* topic, const char* payload, boolean retained);
   boolean publish(const char* topic, const uint8_t * payload, unsigned int plength);
   boolean publish(const char* topic, const uint8_t * payload, unsigned int plength, boolean retained);

Yours is of the structure const char*, String&, size_t&, bool. So it doesn't expect your string but rather a char pointer.