text: #ifndef _PRINTF_H
  #define _PRINTF_H
  
  #include <libc/stdarg.h>
  #include "syscalls.h"
  
  extern int fprintf(int fd, const char* data, ...);
  extern int sprintf(char* dest, const char* data, ...);
  
  #define printf(...) fprintf (1, __VA_ARGS__)
  #define eprintf(...) fprintf (2, __VA_ARGS__)
  
  #endif // _PRINTF_H