main.c

#include <string.h>
#include "freertos/FreeRTOS.h"
#include "esp_wifi.h"
#include "esp_system.h"
#include "esp_event.h"
#include "esp_event_loop.h"
#include "nvs_flash.h"
#include "lwip/api.h"
#include "lwip/tcp.h"

esp_err_t event_handler(void *ctx, system_event_t *event)
{
    return ESP_OK;
}

void app_main(void)
{
    nvs_flash_init();
    tcpip_adapter_init();
    ESP_ERROR_CHECK( esp_event_loop_init(event_handler, NULL) );
    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
    ESP_ERROR_CHECK( esp_wifi_init(&cfg) );
    ESP_ERROR_CHECK( esp_wifi_set_storage(WIFI_STORAGE_RAM) );
    ESP_ERROR_CHECK( esp_wifi_set_mode(WIFI_MODE_STA) );
    wifi_config_t sta_config = {
        .sta = {
            .ssid = "SSID",
            .password = "pass",
            .bssid_set = false
        }
    };
    ESP_ERROR_CHECK( esp_wifi_set_config(WIFI_IF_STA, &sta_config) );
    ESP_ERROR_CHECK( esp_wifi_start() );
    ESP_ERROR_CHECK( esp_wifi_connect() );


    while (1) {
      struct netconn *conn = netconn_new(NETCONN_TCP);
      ip_addr_t remote;
      netconn_gethostbyname("my_ip_here", &remote);

      err_t err = netconn_connect(conn, &remote, 8000);
      if (err != ERR_OK) {
        printf("Connect failed\n");
        vTaskDelay(1000 / portTICK_PERIOD_MS);
        continue;
      }
      printf("Connected!");

      tcp_nagle_disable(conn->pcb.tcp); /* HACK */

      for (int i = 0; i < 10; i++) {
        for (int j = 0; j < 5; j++) {
          const char *data= "OHAI!\n";
          netconn_write(conn, data, strlen(data), NETCONN_NOCOPY);
        }
        vTaskDelay(100 / portTICK_PERIOD_MS);
      }

      printf("Done!");
      netconn_close(conn);
      netconn_delete(conn);
      vTaskDelay(1000 / portTICK_PERIOD_MS);
    }
}