text: #include "../include/definitions.h"
  #include "../include/stdio.h"
  #include "../include/syscalls.h"
  
  #define ENTER			'\n'
  #define TAB				'\t'
  #define SPACE			' '
  #define SCAN_ERROR		0
  
  const char hexDigits [] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
  
  /* getc implementation */
  int getc(int fileDescriptor){
  	byte c;
  	return (__read(fileDescriptor, &c, 1) == 1) ? (byte) c : EOF;
  }
  
  /* putc implementation */
  int putc(int c, int fileDescriptor){
  	int ret;
  	byte aux = BLUE_TEXT;
  	byte character = (byte) c;
  
  	if(c == TAB){
  		putc(' ', fileDescriptor);
  		putc(' ', fileDescriptor);
  		putc(' ', fileDescriptor);
  	} else {
  		ret = (__write(fileDescriptor, &character, 1) == 1) ? c : EOF;
  		__write(fileDescriptor, &aux, 1);
  	}
  	return ret;
  }
  
  int isDigit(char c){
  	if(c >= '0' && c <= '9'){
  		return TRUE;
  	}
  	return FALSE;
  }
  
  int isSpace(char c){
  	if(c == '\n' || c == '\t' || c == ' '){
  		return TRUE;
  	}
  	return FALSE;
  }
  
  int stringToInt(char string, int length){
  	int i, num = 0;
  
  	for(i = 0; i < length; i++){
  		num *= 10;
  		num += (string[i] - '0');
  	}
  	return num;
  }