Added the possibility to get the modem answer from a passthrough call

Author: andreagilardoni

libraries/WiFiS3/src/Modem.cpp

@@ -48,13 +48,17 @@ void ModemClass::end(){
 }
 
 /* -------------------------------------------------------------------------- */
-bool ModemClass::passthrough(const uint8_t *data, size_t size) {
+bool ModemClass::passthrough(const uint8_t *data, size_t size, std::string *response) {
 /* -------------------------------------------------------------------------- */
    _serial->write(data,size);
 
    std::string prompt = DO_NOT_CHECK_CMD, data_res;
    auto res = buf_read(prompt, data_res);
 
+   if(response != nullptr) {
+      *response = data_res;
+   }
+
    if(_serial_debug && _debug_level >= 2) {
       _serial_debug->print("   ANSWER (passthrough): ");
       _serial_debug->println(data_res.c_str());

libraries/WiFiS3/src/Modem.h

@@ -27,7 +27,7 @@ class ModemClass {
   bool write(const std::string &cmd, std::string &str, const char * fmt, ...);
   void write_nowait(const std::string &cmd, std::string &str, const char * fmt, ...);
 
-  bool passthrough(const uint8_t *data, size_t size);
+  bool passthrough(const uint8_t *data, size_t size, std::string *response=nullptr);
   void avoid_trim_results() {
     /* one shot - it works only 1 time the it is necessary to call again this
        funtion */