Testa_File_ESP

#include "FS.h"

void setup()
{
  Serial.begin(115200);
  SPIFFS.begin();
  Serial.println("");
  Serial.println("Abrindo arquivos");
}

void loop()
{
 File f = SPIFFS.open("/f.txt", "w");
if (!f)
{
    Serial.println("file open failed");
}
}