The plan is to create a bigger project and to split the ESP8266 webserver-code over several modules (.h .c files). The main problem is that the ESP8266WebServer server is not declared in the index.h and index.c files.

What I've been trying to do:

Content main.c

#include <ESP8266WiFi.h>
#include "ESP8266WebServer.h"
#include "index.h"

ESP8266WebServer server(80);
const char* ssid =     "test";     
const char* password = "12345678";  

void setup() 
  WiFi.softAP(ssid, password);
  server.on("/", handleRoot(server));           // <-- use of deleted function 'esp8266webserver::ESP8266WebServerTemplate<WiFiServer>::ESP8266WebServerTemplate(const esp8266webserver::ESP8266WebServerTemplate<WiFiServer>&)'

void loop()

Content index.h:

void handleRoot(ESP8266WebServer server); 

const char htmlIndex[] PROGMEM = R"=====(
    <meta http-equiv="content-type" content="text/html;charset=UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <h1>Hello World!</h1>

Content index.c:

#include "webpages/index.h"

void handleRoot(ESP8266WebServer server) 
  Serial.println("GET /");
  server.send(200, "text/html", htmlIndex);

How can I use the ESP8266WebServer server created in the main.c in index.c?


Move the webserver to index.c and include the webserver type:

ESP8266WebServer server(80);

Add an external reference in index.h and include it:

#include "ESP8266WebServer.h"

extern ESP8266WebServer server;

Index.h is included by both main.c and index.c so it will know about server being an ESP8266WebServer type, but does not allocate memory for it; that is done in index.c

This is called a forward reference.

  • I shifted #include "ESP8266WebServer.h" extern ESP8266WebServer server; to main.h and included it in index.c but in the end it is your idea. thx. – kimliv Dec 14 '19 at 0:13
  • Yes, in principle it does not matter where you place the external variable, as long as it is not in a header file (or at least not one that is included twice). Good luck with your project. – Michel Keijzers Dec 14 '19 at 0:22

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