Read from file


Could someone tell me how to read from a text file in C++ in the Arduino sketchbook...I seem to be missing something.


Do you mean read from a text file in your sketch? I'm curious as to the location of this file for it to be accessible by the running app on the arduino. In general, though, the C functions read(), open(), and friends such as fopen() will be helpful, and in C++ the iostream operators such as cin.

I’m trying to pull some info from a text file so that I can use the information. My C++ is a bit rusty but I’m trying something like :

#include <ifstream>
#include <cstdlib>
using std::ifstream;
using std::cout;

void setup()
  ifstream inStream;
  String temp;"test.txt");
  inStream >> str1;
  cout << str1;

Just to see if I can get something from it, but it’s giving me the error:
ifstream: No such file or directory.

Is there a better way to approach this?

I can't remember exactly, but I thought the file objects were in the header file "fstream".

I get the same thing when I try fstream as well.

The Arduino board doesn’t have a filesystem, so there aren’t any files to read from. If you want to write a program that runs on the computer, reads files, and communicates with the sketch running on the Arduino board, you’ll need to use some other development platform (e.g. a standard C++ compiler).