text: #include <stdio.h>
  #include <stdlib.h>
  #include <fcntl.h>
  
  typedef struct{
      char print_buff[1024];
      int vernier;
  }T_PRINFO;
  
  #ifdef REDIR_DEBUG
  char debugbuff[512];
  #endif
  
  T_PRINFO tprino;
  #ifdef REDIR_DEBUG
  #define printf(...) do {    \
      tprino.vernier += sprintf(tprino.print_buff, __VA_ARGS__);      \
      fputs(tprino.print_buff,stdout);\
      sprintf(debugbuff,"tprino.vernier %d\n",tprino.vernier);    \
      fputs(debugbuff,stdout);        \
      }while(0)
  #else
  #define printf(...) do {    \
      tprino.vernier += sprintf(tprino.print_buff, __VA_ARGS__); \
      fputs(tprino.print_buff,stdout);\
  }while(0)
  #endif
  
  
  
  
  int main(void)
  {
      printf("hello world\n");    
      return 0;
  }