glibc/stdio/stdio.h

/* Copyright (C) 1991, 92, 93, 94, 95, 96, 97 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., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

/*
 *	ISO C 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 ((char *__buf, size_t __bufsize,
					__const char *__dir,
					__const char *__pfx,
					int __dir_search,
					size_t *__lenptr,
					FILE **__streamptr));


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


/* For thread safe I/O functions we need a lock in each stream.  We
   keep the type opaque here.  */
struct __stdio_lock;

/* 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 ((int) 0xfedabeeb)	/* Magic number to fill `__magic'.  */
#define	_GLUEMAGIC ((int) 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.  */
  struct __stdio_lock *__lock;	/* Pointer to associated lock.  */
};


/* 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 &&							      \
   ({ if (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	Minimum 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;
#ifdef __STRICT_ANSI__
/* ANSI says these are macros; satisfy pedants.  */
#define	stdin	stdin
#define	stdout	stdout
#define	stderr	stderr
#endif


/* 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_REENTRANT
/* This is the reentrant variant of `tmpnam'.  The only difference is
   that it does not allow S to be NULL.  */
extern char *tmpnam_r __P ((char *__s));
#endif


#if defined __USE_SVID || defined __USE_XOPEN
/* 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.  */
extern int fclose __P ((FILE *__stream));
/* Flush STREAM, or all streams if STREAM is NULL.  */
extern int fflush __P ((FILE *__stream));

#ifdef __USE_GNU
/* Close all streams.  */
extern int __fcloseall __P ((void));
extern int fcloseall __P ((void));
#endif


/* 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 *__restrict __filename,
			   __const char *__rstrict __modes,
			   FILE *__restrict __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.  */
extern FILE *fopencookie __P ((__ptr_t __magic_cookie, __const char *__modes,
			       __io_functions __io_funcs));

/* Create a new stream that refers to a memory buffer.  */
extern FILE *fmemopen __P ((__ptr_t __s, size_t __len, __const char *__modes));

/* Open a stream that writes into a malloc'd buffer that is expanded as
   necessary.  *BUFLOC and *SIZELOC are updated with the buffer's location
   and the number of characters written on fflush or fclose.  */
extern FILE *open_memstream __P ((char **__bufloc, size_t *__sizeloc));
#endif


/* If BUF is NULL, make STREAM unbuffered.
   Else make it use buffer BUF, of size BUFSIZ.  */
extern void setbuf __P ((FILE *__restrict __stream, char *__restrict __buf));
/* Make STREAM use buffering mode MODE.
   If BUF is not NULL, use N bytes of it for buffering;
   else allocate an internal buffer N bytes long.  */
extern int setvbuf __P ((FILE *__restrict __stream, char *__restrict __buf,
			 int __modes, size_t __n));

#ifdef	__USE_BSD
/* If BUF is NULL, make STREAM unbuffered.
   Else make it use SIZE bytes of BUF for buffering.  */
extern void setbuffer __P ((FILE *__stream, char *__buf, size_t __size));

/* Make STREAM line-buffered.  */
extern void setlinebuf __P ((FILE *__stream));
#endif


/* Write formatted output to STREAM.  */
extern int fprintf __P ((FILE *__restrict __stream,
			 __const char *__restrict __format, ...));
/* Write formatted output to stdout.  */
extern int printf __P ((__const char *__restrict __format, ...));
/* Write formatted output to S.  */
extern int sprintf __P ((char *__restrict __s,
			 __const char *__restrict __format, ...));

/* Write formatted output to S from argument list ARG.  */
extern int vfprintf __P ((FILE *__restrict __s,
			  __const char *__restrict __format,
			  __gnuc_va_list __arg));
/* Write formatted output to stdout from argument list ARG.  */
extern int vprintf __P ((__const char *__restrict __format,
			 __gnuc_va_list __arg));
/* Write formatted output to S from argument list ARG.  */
extern int vsprintf __P ((char *__restrict __s,
			  __const char *__restrict __format,
			  __gnuc_va_list __arg));

#ifdef	__OPTIMIZE__
extern __inline int
vprintf (const char *__restrict __fmt, __gnuc_va_list __arg)
{
  return vfprintf (stdout, __fmt, __arg);
}
#endif /* Optimizing.  */

#ifdef	__USE_GNU
/* Maximum chars of output to write in MAXLEN.  */
extern int __snprintf __P ((char *__s, size_t __maxlen,
			    __const char *__format, ...));
extern int snprintf __P ((char *__s, size_t __maxlen,
			  __const char *__format, ...));

extern int __vsnprintf __P ((char *__s, size_t __maxlen,
			     __const char *__format, __gnuc_va_list __arg));
extern int vsnprintf __P ((char *__s, size_t __maxlen,
			   __const char *__format, __gnuc_va_list __arg));

/* Write formatted output to a string dynamically allocated with `malloc'.
   Store the address of the string in *PTR.  */
extern int vasprintf __P ((char **__ptr, __const char *__f,
			   __gnuc_va_list __arg));
extern int asprintf __P ((char **__ptr, __const char *__fmt, ...));

/* Write formatted output to a file descriptor.  */
extern int vdprintf __P ((int __fd, __const char *__fmt,
			  __gnuc_va_list __arg));
extern int dprintf __P ((int __fd, __const char *__fmt, ...));
#endif


/* Read formatted input from STREAM.  */
extern int fscanf __P ((FILE *__restrict __stream,
			__const char *__restrict __format, ...));
/* Read formatted input from stdin.  */
extern int scanf __P ((__const char *__restrict __format, ...));
/* Read formatted input from S.  */
extern int sscanf __P ((__const char *__restrict __s,
			__const char *__restrict __format, ...));

#ifdef	__USE_GNU
/* Read formatted input from S into argument list ARG.  */
extern int __vfscanf __P ((FILE *__s, __const char *__format,
			   __gnuc_va_list __arg));
extern int vfscanf __P ((FILE *__s, __const char *__format,
			 __gnuc_va_list __arg));

/* Read formatted input from stdin into argument list ARG.  */
extern int __vscanf __P ((__const char *__format, __gnuc_va_list __arg));
extern int vscanf __P ((__const char *__format, __gnuc_va_list __arg));

/* Read formatted input from S into argument list ARG.  */
extern int __vsscanf __P ((__const char *__s, __const char *__format,
			   __gnuc_va_list __arg));
extern int vsscanf __P ((__const char *__s, __const char *__format,
			 __gnuc_va_list __arg));


#ifdef	__OPTIMIZE__
extern __inline int
vfscanf (FILE *__s, const char *__fmt, __gnuc_va_list __arg)
{
  return __vfscanf (__s, __fmt, __arg);
}
extern __inline int
vscanf (const char *__fmt, __gnuc_va_list __arg)
{
  return __vfscanf (stdin, __fmt, __arg);
}
extern __inline int
vsscanf (const char *__s, const char *__fmt, __gnuc_va_list __arg)
{
  return __vsscanf (__s, __fmt, __arg);
}
#endif /* Optimizing.  */
#endif /* Use GNU.  */


/* This does actual reading when necessary, filling STREAM's
   buffer and returning the first character in it.  */
extern int __fillbf __P ((FILE *__stream));


/* Read a character from STREAM.  */
extern int fgetc __P ((FILE *__stream));
extern int getc __P ((FILE *__stream));

/* Read a character from stdin.  */
extern int getchar __P ((void));

/* The C standard explicitly says this can
   re-evaluate its argument, so it does. */
#define	__getc(stream)							      \
  ((stream)->__bufp < (stream)->__get_limit ?				      \
   (int) ((unsigned char) *(stream)->__bufp++) : __fillbf(stream))

/* The C standard explicitly says this is a macro,
   so we always do the optimization for it.  */
#define	getc(stream)	__getc(stream)

#ifdef	__OPTIMIZE__
extern __inline int
getchar (void)
{
  return __getc (stdin);
}
#endif /* Optimizing.  */


/* Write a character to STREAM.  */
extern int fputc __P ((int __c, FILE *__stream));
extern int putc __P ((int __c, FILE *__stream));

/* Write a character to stdout.  */
extern int putchar __P ((int __c));


/* The C standard explicitly says this can
   re-evaluate its arguments, so it does.  */
#define	__putc(c, stream)						      \
  ((stream)->__bufp < (stream)->__put_limit ?				      \
   (int) (unsigned char) (*(stream)->__bufp++ = (unsigned char) (c)) :	      \
   __flshfp ((stream), (unsigned char) (c)))

/* The C standard explicitly says this can be a macro,
   so we always do the optimization for it.  */
#define	putc(c, stream)	__putc ((c), (stream))

#ifdef __OPTIMIZE__
extern __inline int
putchar (int __c)
{
  return __putc (__c, stdout);
}
#endif


#if defined(__USE_SVID) || defined(__USE_MISC)
/* Get a word (int) from STREAM.  */
extern int getw __P ((FILE *__stream));

/* Write a word (int) to STREAM.  */
extern int putw __P ((int __w, FILE *__stream));
#endif


/* Get a newline-terminated string of finite length from STREAM.  */
extern char *fgets __P ((char *__restrict __s, int __n,
			 FILE *__restrict __stream));

/* Get a newline-terminated string from stdin, removing the newline.
   DO NOT USE THIS FUNCTION!!  There is no limit on how much it will read.  */
extern char *gets __P ((char *__s));


#ifdef	__USE_GNU
#include <sys/types.h>

/* Read up to (and including) a DELIMITER from STREAM into *LINEPTR
   (and null-terminate it). *LINEPTR is a pointer returned from malloc (or
   NULL), pointing to *N characters of space.  It is realloc'd as
   necessary.  Returns the number of characters read (not including the
   null terminator), or -1 on error or EOF.  */
ssize_t __getdelim __P ((char **__lineptr, size_t *__n,
			 int __delimiter, FILE *__stream));
ssize_t getdelim __P ((char **__lineptr, size_t *__n,
		       int __delimiter, FILE *__stream));

/* Like `getdelim', but reads up to a newline.  */
ssize_t __getline __P ((char **__lineptr, size_t *__n, FILE *__stream));
ssize_t getline __P ((char **__lineptr, size_t *__n, FILE *__stream));

#ifdef	__OPTIMIZE__
extern __inline ssize_t
getline (char **__lineptr, size_t *__n, FILE *__stream)
{
  return __getdelim (__lineptr, __n, '\n', __stream);
}
#endif /* Optimizing.  */
#endif


/* Write a string to STREAM.  */
extern int fputs __P ((__const char *__restrict __s,
		       FILE *__restrict __stream));
/* Write a string, followed by a newline, to stdout.  */
extern int puts __P ((__const char *__s));


/* Push a character back onto the input buffer of STREAM.  */
extern int ungetc __P ((int __c, FILE *__stream));


/* Read chunks of generic data from STREAM.  */
extern size_t fread __P ((__ptr_t __restrict __ptr, size_t __size,
			  size_t __n, FILE *__restrict __stream));
/* Write chunks of generic data to STREAM.  */
extern size_t fwrite __P ((__const __ptr_t __restrict __ptr, size_t __size,
			   size_t __n, FILE *__restrict __s));


/* Seek to a certain position on STREAM.  */
extern int fseek __P ((FILE *__stream, long int __off, int __whence));
/* Return the current position of STREAM.  */
extern long int ftell __P ((FILE *__stream));
/* Rewind to the beginning of STREAM.  */
extern void rewind __P ((FILE *__stream));

/* Get STREAM's position.  */
extern int fgetpos __P ((FILE *__restrict __stream, fpos_t *__restrict __pos));
/* Set STREAM's position.  */
extern int fsetpos __P ((FILE *__stream, __const fpos_t *__pos));


/* Clear the error and EOF indicators for STREAM.  */
extern void clearerr __P ((FILE *__stream));
/* Return the EOF indicator for STREAM.  */
extern int feof __P ((FILE *__stream));
/* Return the error indicator for STREAM.  */
extern int ferror __P ((FILE *__stream));

#ifdef	__OPTIMIZE__
#define	feof(stream)	((stream)->__eof != 0)
#define	ferror(stream)	((stream)->__error != 0)
#endif /* Optimizing.  */


/* Print a message describing the meaning of the value of errno.  */
extern void perror __P ((__const char *__s));

#ifdef	__USE_BSD
extern int sys_nerr;
extern const char *const sys_errlist[];
#endif
#ifdef	__USE_GNU
extern int _sys_nerr;
extern const char *const _sys_errlist[];
#endif


#ifdef	__USE_POSIX
/* Return the system file descriptor for STREAM.  */
extern int fileno __P ((FILE *__stream));
#endif /* Use POSIX.  */


#if (defined (__USE_POSIX2) || defined(__USE_SVID) || defined(__USE_BSD) || \
     defined(__USE_MISC))
/* Create a new stream connected to a pipe running the given command.  */
extern FILE *popen __P ((__const char *__command, __const char *__modes));

/* Close a stream opened by popen and return the status of its child.  */
extern int pclose __P ((FILE *__stream));
#endif


#ifdef	__USE_POSIX
/* Return the name of the controlling terminal.  */
extern char *ctermid __P ((char *__s));
#endif


#ifdef __USE_XOPEN
/* Return the name of the current user.  */
extern char *cuserid __P ((char *__s));
#endif


#ifdef	__USE_GNU
struct obstack;			/* See <obstack.h>.  */

/* Open a stream that writes to OBSTACK.  */
extern FILE *open_obstack_stream __P ((struct obstack *__obstack));

/* Write formatted output to an obstack.  */
extern int obstack_printf __P ((struct obstack *__obstack,
				__const char *__format, ...));
extern int obstack_vprintf __P ((struct obstack *__obstack,
				 __const char *__format,
				 __gnuc_va_list __args));
#endif


__END_DECLS

#endif /* <stdio.h> included.  */

#endif /* stdio.h  */