char msg[32];

void incr_ref(char*& ptr) {  // reference to pointer
  ptr++;
}

char* incr_ret(char* ptr) {
  return ptr + 1;  // or return ++ptr;
}

void incr(char** ptr) {
  (*ptr)++;  // increment the pointer that ptr points to
}

void setup() {
  Serial.begin(9600);
    strcpy(msg, "hello");
    char* str = msg;  // str points to "hello"
    Serial.println(str);
    
    incr(&str);       // pass address of str
    Serial.println(str);

    incr_ref(str);
    Serial.println(str);

    str = incr_ret(str);
    Serial.println(str);

}

void loop() {
  // put your main code here, to run repeatedly:

}