text: #ifndef _STDIO_IMPL_H
  #define _STDIO_IMPL_H
  
  #include <stdio.h>
  #include "syscall.h"
  #include "libc.h"
  
  #define UNGET 8
  
  #define FFINALLOCK(f) ((f)->lock>=0 ? __lockfile((f)) : 0)
  #define FLOCK(f) int __need_unlock = ((f)->lock>=0 ? __lockfile((f)) : 0)
  #define FUNLOCK(f) do { if (__need_unlock) __unlockfile((f)); } while (0)
  
  #define F_PERM 1
  #define F_NORD 4
  #define F_NOWR 8
  #define F_EOF 16
  #define F_ERR 32
  #define F_SVB 64
  #define F_APP 128
  
  struct _IO_FILE {
  	unsigned flags;
  	unsigned char *rpos, *rend;
  	int (*close)(FILE *);
  	unsigned char *wend, *wpos;
  	unsigned char *mustbezero_1;
  	unsigned char *wbase;
  	size_t (*read)(FILE *, unsigned char *, size_t);
  	size_t (*write)(FILE *, const unsigned char *, size_t);
  	off_t (*seek)(FILE *, off_t, int);
  	unsigned char *buf;
  	size_t buf_size;
  	FILE *prev, *next;
  	int fd;
  	int pipe_pid;
  	long lockcount;
  	short dummy3;
  	signed char mode;
  	signed char lbf;
  	volatile int lock;
  	volatile int waiters;
  	void *cookie;
  	off_t off;
  	char *getln_buf;
  	void *mustbezero_2;
  	unsigned char *shend;
  	off_t shlim, shcnt;
  	FILE *prev_locked, *next_locked;
  	struct __locale_struct *locale;
  };
  
  size_t __stdio_read(FILE *, unsigned char *, size_t);
  size_t __stdio_write(FILE *, const unsigned char *, size_t);
  size_t __stdout_write(FILE *, const unsigned char *, size_t);
  off_t __stdio_seek(FILE *, off_t, int);
  int __stdio_close(FILE *);
  
  size_t __string_read(FILE *, unsigned char *, size_t);
  
  int __toread(FILE *);
  int __towrite(FILE *);
  
  #if 0 //defined(__PIC__) && (100*__GNUC__+__GNUC_MINOR__ >= 303)
  __attribute__((visibility("protected")))
  #endif
  int __overflow(FILE *, int), __uflow(FILE *);
  
  int __fseeko(FILE *, off_t, int);
  int __fseeko_unlocked(FILE *, off_t, int);
  off_t __ftello(FILE *);
  off_t __ftello_unlocked(FILE *);
  size_t __fwritex(const unsigned char *, size_t, FILE *);
  int __putc_unlocked(int, FILE *);
  
  FILE *__fdopen(int, const char *);
  int __fmodeflags(const char *);
  
  FILE *__ofl_add(FILE *f);
  FILE **__ofl_lock(void);
  void __ofl_unlock(void);
  
  #define feof(f) ((f)->flags & F_EOF)
  #define ferror(f) ((f)->flags & F_ERR)
  
  #define getc_unlocked(f) \
  	( ((f)->rpos < (f)->rend) ? *(f)->rpos++ : __uflow((f)) )
  
  #define putc_unlocked(c, f) \
  	( ((unsigned char)(c)!=(f)->lbf && (f)->wpos<(f)->wend) \
  	? *(f)->wpos++ = (c) : __overflow((f),(c)) )
  
  /* Caller-allocated FILE * operations */
  FILE *__fopen_rb_ca(const char *, FILE *, unsigned char *, size_t);
  int __fclose_ca(FILE *);
  
  #endif
  