Hi luismaya,
What message are you getting in the serial monitor? Are you successfully reading from file? You can also use C to code on Galileo using a sketch via the Arduino IDE. It is a lot easier to read and write to a file instead of using the SD.h library. Here is a sample code to include in your sketch.
datafile= fopen( "/tmp/datafile" , "r"); if (datafile) { while (fgets(output, 100, datafile) != NULL) ; fclose(datafile); } data= atoi(output);
Also, don't forget to declare your variable at the beginning of the sketch. since you are using integers, this code should get you started.
char output[100]; FILE * datafile; int data;
If you are more comfortable using the SD library I can also help you with that, i just need to know what messages you are getting in the Serial Monitor.
Regards,
Intel_Jesus