ESP8266 Community Forum

- Tue Dec 20, 2016 6:11 pm #59765 Hi,

I need to check if connection to WIFI has been lost so I decided to check the number of connected clients.

I found this topic: viewtopic.php?f=6&t=8402 and registering a callback seems to be the best option. I have a problem though - I am not sure how to do it. I'm using Arduino IDE to program the board ESP8266 12E.

My includes:

Code: Select all#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>

I tried something like this:

Code: Select allvoid wifi_handle_event_cb(System_Event_t *evt){
  switch (evt->event){
    case EVENT_STAMODE_CONNECTED:
      //there is new connection
      break;
    case EVENT_STAMODE_DISCONNECTED:
      //connection has been lost
      break;
    default:
      break;
  }
}

void setup() {
    delay(1000);
    Serial.begin(9600);
    wifi_set_event_handler_cb(wifi_handle_event_cb);
    WiFi.softAP(ssid, password);
    IPAddress apip = WiFi.softAPIP();
    server.begin();
}


I get the following errors:

Code: Select allerror: variable or field 'wifi_handle_event_cb' declared void
error: 'System_Event_t' was not declared in this scope
error: 'evt' was not declared in this scope


It looks like I am missing some includes, I tried adding different ones though and it didn't help.

- Wed Dec 21, 2016 7:00 am #59785 It is located in the SDK :

Code: Select allextern "C" {
#include "user_interface.h"
}


- Wed Dec 21, 2016 11:16 am #59789

It is located in the SDK :

Code: Select allextern "C" {
#include "user_interface.h"
}


I tried adding that and I'm getting the same error

- Wed Dec 21, 2016 2:20 pm #59797 Strange, it is clearly there in that file at line 462.

https://github.com/esp8266/Arduino/blob ... #L462-L465

Code: Select alltypedef struct _esp_event {
    uint32 event;
    Event_Info_u event_info;
} System_Event_t;