stdio.h

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/* Copyright (C) 1991, 1992, 1993, 1994 Free Software Foundation, Inc.
This file is part of the GNU C Library.

The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.

The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA.  */

/*
 *	ANSI Standard: 4.9 INPUT/OUTPUT	<stdio.h>
 */

#ifndef	_STDIO_H

#if	!defined(__need_FILE)
#define	_STDIO_H	1
#include <features.h>

__BEGIN_DECLS

#define	__need_size_t
#define	__need_NULL
#include <stddef.h>

#define	__need___va_list
#include <stdarg.h>
#ifndef	__GNUC_VA_LIST
#define	__gnuc_va_list	__ptr_t
#endif

#include <gnu/types.h>
#endif /* Don't need FILE.  */
#undef	__need_FILE


#ifndef	__FILE_defined

/* The opaque type of streams.  */
typedef struct __stdio_file FILE;

#define	__FILE_defined	1
#endif /* FILE not defined.  */


#ifdef	_STDIO_H

/* The type of the second argument to `fgetpos' and `fsetpos'.  */
typedef __off_t fpos_t;

/* The mode of I/O, as given in the MODE argument to fopen, etc.  */
typedef struct
{
  unsigned int __read:1;	/* Open for reading.  */
  unsigned int __write:1;	/* Open for writing.  */
  unsigned int __append:1;	/* Open for appending.  */
  unsigned int __binary:1;	/* Opened binary.  */
  unsigned int __create:1;	/* Create the file.  */
  unsigned int __exclusive:1;	/* Error if it already exists.  */
  unsigned int __truncate:1;	/* Truncate the file on opening.  */
} __io_mode;


/* Functions to do I/O and file management for a stream.  */

/* Read NBYTES bytes from COOKIE into a buffer pointed to by BUF.
   Return number of bytes read.  */
typedef __ssize_t __io_read_fn __P ((__ptr_t __cookie, char *__buf,
				     size_t __nbytes));

/* Write N bytes pointed to by BUF to COOKIE.  Write all N bytes
   unless there is an error.  Return number of bytes written, or -1 if
   there is an error without writing anything.  If the file has been
   opened for append (__mode.__append set), then set the file pointer
   to the end of the file and then do the write; if not, just write at
   the current file pointer.  */
typedef __ssize_t __io_write_fn __P ((__ptr_t __cookie, __const char *__buf,
				      size_t __n));

/* Move COOKIE's file position to *POS bytes from the
   beginning of the file (if W is SEEK_SET),
   the current position (if W is SEEK_CUR),
   or the end of the file (if W is SEEK_END).
   Set *POS to the new file position.
   Returns zero if successful, nonzero if not.  */
typedef int __io_seek_fn __P ((__ptr_t __cookie, fpos_t *__pos, int __w));

/* Close COOKIE.  */
typedef int __io_close_fn __P ((__ptr_t __cookie));

/* Return the file descriptor associated with COOKIE,
   or -1 on error.  There need not be any associated file descriptor.  */
typedef int __io_fileno_fn __P ((__ptr_t __cookie));

#ifdef __USE_GNU
/* User-visible names for the above.  */
typedef __io_read_fn cookie_read_function_t;
typedef __io_write_fn cookie_write_function_t;
typedef __io_seek_fn cookie_seek_function_t;
typedef __io_close_fn cookie_close_function_t;
typedef __io_fileno_fn cookie_fileno_function_t;
#endif

/* Low level interface, independent of FILE representation.  */
#if defined (__USE_GNU) && !defined (_LIBC)
/* Define the user-visible type, with user-friendly member names.  */
typedef struct
{
  __io_read_fn *read;		/* Read bytes.  */
  __io_write_fn *write;		/* Write bytes.  */
  __io_seek_fn *seek;		/* Seek/tell file position.  */
  __io_close_fn *close;		/* Close file.  */
  __io_fileno_fn *fileno;	/* Return file descriptor.  */
} cookie_io_functions_t;
/* This name is still used in the prototypes in this file.  */
typedef cookie_io_functions_t __io_functions;
#else
/* Stick to ANSI-safe names.  */
typedef struct
{
  __io_read_fn *__read;		/* Read bytes.  */
  __io_write_fn *__write;	/* Write bytes.  */
  __io_seek_fn *__seek;		/* Seek/tell file position.  */
  __io_close_fn *__close;	/* Close file.  */
  __io_fileno_fn *__fileno;	/* Return file descriptor.  */
} __io_functions;
#endif

/* Higher level interface, dependent on FILE representation.  */
typedef struct
{
  /* Make room in the input buffer.  */
  int (*__input) __P ((FILE *__stream));
  /* Make room in the output buffer.  */
  void (*__output) __P ((FILE *__stream, int __c));
} __room_functions;

extern __const __io_functions __default_io_functions;
extern __const __room_functions __default_room_functions;


/* Default close function.  */
extern __io_close_fn __stdio_close;
/* Open FILE with mode M, store cookie in *COOKIEPTR.  */
extern int __stdio_open __P ((__const char *__file, __io_mode __m,
			      __ptr_t *__cookieptr));
/* Put out an error message for when stdio needs to die.  */
extern void __stdio_errmsg __P ((__const char *__msg, size_t __len));
/* Generate a unique file name (and possibly open it with mode "w+b").  */
extern char *__stdio_gen_tempname __P ((__const char *__dir,
					__const char *__pfx,
					int __dir_search,
					size_t *__lenptr,
					FILE **__streamptr));


/* Print out MESSAGE on the error output and abort.  */
extern __NORETURN void __libc_fatal __P ((__const char *__message));


/* The FILE structure.  */
struct __stdio_file
{
  /* Magic number for validation.  Must be negative in open streams
     for the glue to Unix stdio getc/putc to work.
     NOTE: stdio/glue.c has special knowledge of these first four members.  */
  int __magic;
#define	_IOMAGIC	0xfedabeeb	/* Magic number to fill `__magic'.  */
#define	_GLUEMAGIC	0xfeedbabe	/* Magic for glued Unix streams.  */

  char *__bufp;			/* Pointer into the buffer.  */
  char *__get_limit;		/* Reading limit.  */
  char *__put_limit;		/* Writing limit.  */

  char *__buffer;		/* Base of buffer.  */
  size_t __bufsize;		/* Size of the buffer.  */
  __ptr_t __cookie;		/* Magic cookie.  */
  __io_mode __mode;		/* File access mode.  */
  __io_functions __io_funcs;	/* I/O functions.  */
  __room_functions __room_funcs;/* I/O buffer room functions.  */
  fpos_t __offset;		/* Current file position.  */
  fpos_t __target;		/* Target file position.  */
  FILE *__next;			/* Next FILE in the linked list.  */
  char *__pushback_bufp;	/* Old bufp if char pushed back.  */
  unsigned char __pushback;	/* Pushed-back character.  */
  unsigned int __pushed_back:1;	/* A char has been pushed back.  */
  unsigned int __eof:1;		/* End of file encountered.  */
  unsigned int __error:1;	/* Error encountered.  */
  unsigned int __userbuf:1;	/* Buffer from user (should not be freed).  */
  unsigned int __linebuf:1;	/* Flush on newline.  */
  unsigned int __linebuf_active:1; /* put_limit is not really in use.  */
  unsigned int __seen:1;	/* This stream has been seen.  */
  unsigned int __ispipe:1;	/* Nonzero if opened by popen.  */
};


/* All macros used internally by other macros here and by stdio functions begin
   with `__'.  All of these may evaluate their arguments more than once.  */


/* Nonzero if STREAM is a valid stream.
   STREAM must be a modifiable lvalue (wow, I got to use that term).
   See stdio/glue.c for what the confusing bit is about.  */
#define	__validfp(stream)						      \
  (stream != NULL &&							      \
   ((stream->__magic == _GLUEMAGIC &&					      \
     (stream = *(((struct { int __magic; FILE **__p; } *) stream)->__p))),    \
    (stream->__magic == _IOMAGIC)))

/* Clear the error and EOF indicators of STREAM.  */
#define	__clearerr(stream)	((stream)->__error = (stream)->__eof = 0)

/* Nuke STREAM, making it unusable but available for reuse.  */
extern void __invalidate __P ((FILE *__stream));

/* Make sure STREAM->__offset and STREAM->__target are initialized.
   Returns 0 if successful, or EOF on
   error (but doesn't set STREAM->__error).  */
extern int __stdio_check_offset __P ((FILE *__stream));


/* The possibilities for the third argument to `setvbuf'.  */
#define _IOFBF	0x1		/* Full buffering.  */
#define _IOLBF	0x2		/* Line buffering.  */
#define _IONBF	0x4		/* No buffering.  */


/* Default buffer size.  */
#define	BUFSIZ	1024


/* End of file character.
   Some things throughout the library rely on this being -1.  */
#define	EOF	(-1)


/* The possibilities for the third argument to `fseek'.
   These values should not be changed.  */
#define	SEEK_SET	0	/* Seek from beginning of file.  */
#define	SEEK_CUR	1	/* Seek from current position.  */
#define	SEEK_END	2	/* Seek from end of file.  */


#ifdef	__USE_SVID
/* Default path prefix for `tempnam' and `tmpnam'.  */
#define	P_tmpdir	"/usr/tmp"
#endif


/* Get the values:
   L_tmpnam	How long an array of chars must be to be passed to `tmpnam'.
   TMP_MAX	The minimum number of unique filenames generated by tmpnam
   		(and tempnam when it uses tmpnam's name space),
		or tempnam (the two are separate).
   L_ctermid	How long an array to pass to `ctermid'.
   L_cuserid	How long an array to pass to `cuserid'.
   FOPEN_MAX	Mininum number of files that can be open at once.
   FILENAME_MAX	Maximum length of a filename.  */
#include <stdio_lim.h>


/* All the known streams are in a linked list
   linked by the `next' field of the FILE structure.  */
extern FILE *__stdio_head;	/* Head of the list.  */

/* Standard streams.  */
extern FILE *stdin, *stdout, *stderr;


/* Remove file FILENAME.  */
extern int remove __P ((__const char *__filename));
/* Rename file OLD to NEW.  */
extern int rename __P ((__const char *__old, __const char *__new));


/* Create a temporary file and open it read/write.  */
extern FILE *tmpfile __P ((void));
/* Generate a temporary filename.  */
extern char *tmpnam __P ((char *__s));


#ifdef	__USE_SVID
/* Generate a unique temporary filename using up to five characters of PFX
   if it is not NULL.  The directory to put this file in is searched for
   as follows: First the environment variable "TMPDIR" is checked.
   If it contains the name of a writable directory, that directory is used.
   If not and if DIR is not NULL, that value is checked.  If that fails,
   P_tmpdir is tried and finally "/tmp".  The storage for the filename
   is allocated by `malloc'.  */
extern char *tempnam __P ((__const char *__dir, __const char *__pfx));
#endif


/* This performs actual output when necessary, flushing
   STREAM's buffer and optionally writing another character.  */
extern int __flshfp __P ((FILE *__stream, int __c));


/* Close STREAM, or all streams if STREAM is NULL.  */
extern int fclose __P ((FILE *__stream));
/* Flush STREAM, or all streams if STREAM is NULL.  */
extern int fflush __P ((FILE *__stream));


/* Open a file and create a new stream for it.  */
extern FILE *fopen __P ((__const char *__filename, __const char *__modes));
/* Open a file, replacing an existing stream with it. */
extern FILE *freopen __P ((__const char *__filename,
			   __const char *__modes, FILE *__stream));

/* Return a new, zeroed, stream.
   You must set its cookie and io_mode.
   The first operation will give it a buffer unless you do.
   It will also give it the default functions unless you set the `seen' flag.
   The offset is set to -1, meaning it will be determined by doing a
   stationary seek.  You can set it to avoid the initial tell call.
   The target is set to -1, meaning it will be set to the offset
   before the target is needed.
   Returns NULL if a stream can't be created.  */
extern FILE *__newstream __P ((void));

#ifdef	__USE_POSIX
/* Create a new stream that refers to an existing system file descriptor.  */
extern FILE *fdopen __P ((int __fd, __const char *__modes));
#endif

#ifdef	__USE_GNU
/* Create a new stream that refers to the given magic cookie,
   and uses the given functions for input and output.  */