update from main archive 960927
[glibc.git] / stdio / stdio.h
blob807262531294d0ecc07966a96c5e2091d8875deb
1 /* Copyright (C) 1991, 92, 93, 94, 95, 96 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Library General Public License as
6 published by the Free Software Foundation; either version 2 of the
7 License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Library General Public License for more details.
14 You should have received a copy of the GNU Library General Public
15 License along with the GNU C Library; see the file COPYING.LIB. If
16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
17 Cambridge, MA 02139, USA. */
20 * ANSI Standard: 4.9 INPUT/OUTPUT <stdio.h>
23 #ifndef _STDIO_H
25 #if !defined(__need_FILE)
26 #define _STDIO_H 1
27 #include <features.h>
29 __BEGIN_DECLS
31 #define __need_size_t
32 #define __need_NULL
33 #include <stddef.h>
35 #define __need___va_list
36 #include <stdarg.h>
37 #ifndef __GNUC_VA_LIST
38 #define __gnuc_va_list __ptr_t
39 #endif
41 #include <gnu/types.h>
42 #endif /* Don't need FILE. */
43 #undef __need_FILE
46 #ifndef __FILE_defined
48 /* The opaque type of streams. */
49 typedef struct __stdio_file FILE;
51 #define __FILE_defined 1
52 #endif /* FILE not defined. */
55 #ifdef _STDIO_H
57 /* The type of the second argument to `fgetpos' and `fsetpos'. */
58 typedef __off_t fpos_t;
60 /* The mode of I/O, as given in the MODE argument to fopen, etc. */
61 typedef struct
63 unsigned int __read:1; /* Open for reading. */
64 unsigned int __write:1; /* Open for writing. */
65 unsigned int __append:1; /* Open for appending. */
66 unsigned int __binary:1; /* Opened binary. */
67 unsigned int __create:1; /* Create the file. */
68 unsigned int __exclusive:1; /* Error if it already exists. */
69 unsigned int __truncate:1; /* Truncate the file on opening. */
70 } __io_mode;
73 /* Functions to do I/O and file management for a stream. */
75 /* Read NBYTES bytes from COOKIE into a buffer pointed to by BUF.
76 Return number of bytes read. */
77 typedef __ssize_t __io_read_fn __P ((__ptr_t __cookie, char *__buf,
78 size_t __nbytes));
80 /* Write N bytes pointed to by BUF to COOKIE. Write all N bytes
81 unless there is an error. Return number of bytes written, or -1 if
82 there is an error without writing anything. If the file has been
83 opened for append (__mode.__append set), then set the file pointer
84 to the end of the file and then do the write; if not, just write at
85 the current file pointer. */
86 typedef __ssize_t __io_write_fn __P ((__ptr_t __cookie, __const char *__buf,
87 size_t __n));
89 /* Move COOKIE's file position to *POS bytes from the
90 beginning of the file (if W is SEEK_SET),
91 the current position (if W is SEEK_CUR),
92 or the end of the file (if W is SEEK_END).
93 Set *POS to the new file position.
94 Returns zero if successful, nonzero if not. */
95 typedef int __io_seek_fn __P ((__ptr_t __cookie, fpos_t *__pos, int __w));
97 /* Close COOKIE. */
98 typedef int __io_close_fn __P ((__ptr_t __cookie));
100 /* Return the file descriptor associated with COOKIE,
101 or -1 on error. There need not be any associated file descriptor. */
102 typedef int __io_fileno_fn __P ((__ptr_t __cookie));
104 #ifdef __USE_GNU
105 /* User-visible names for the above. */
106 typedef __io_read_fn cookie_read_function_t;
107 typedef __io_write_fn cookie_write_function_t;
108 typedef __io_seek_fn cookie_seek_function_t;
109 typedef __io_close_fn cookie_close_function_t;
110 typedef __io_fileno_fn cookie_fileno_function_t;
111 #endif
113 /* Low level interface, independent of FILE representation. */
114 #if defined (__USE_GNU) && !defined (_LIBC)
115 /* Define the user-visible type, with user-friendly member names. */
116 typedef struct
118 __io_read_fn *read; /* Read bytes. */
119 __io_write_fn *write; /* Write bytes. */
120 __io_seek_fn *seek; /* Seek/tell file position. */
121 __io_close_fn *close; /* Close file. */
122 __io_fileno_fn *fileno; /* Return file descriptor. */
123 } cookie_io_functions_t;
124 /* This name is still used in the prototypes in this file. */
125 typedef cookie_io_functions_t __io_functions;
126 #else
127 /* Stick to ANSI-safe names. */
128 typedef struct
130 __io_read_fn *__read; /* Read bytes. */
131 __io_write_fn *__write; /* Write bytes. */
132 __io_seek_fn *__seek; /* Seek/tell file position. */
133 __io_close_fn *__close; /* Close file. */
134 __io_fileno_fn *__fileno; /* Return file descriptor. */
135 } __io_functions;
136 #endif
138 /* Higher level interface, dependent on FILE representation. */
139 typedef struct
141 /* Make room in the input buffer. */
142 int (*__input) __P ((FILE *__stream));
143 /* Make room in the output buffer. */
144 void (*__output) __P ((FILE *__stream, int __c));
145 } __room_functions;
147 extern __const __io_functions __default_io_functions;
148 extern __const __room_functions __default_room_functions;
151 /* Default close function. */
152 extern __io_close_fn __stdio_close;
153 /* Open FILE with mode M, store cookie in *COOKIEPTR. */
154 extern int __stdio_open __P ((__const char *__file, __io_mode __m,
155 __ptr_t *__cookieptr));
156 /* Put out an error message for when stdio needs to die. */
157 extern void __stdio_errmsg __P ((__const char *__msg, size_t __len));
158 /* Generate a unique file name (and possibly open it with mode "w+b"). */
159 extern char *__stdio_gen_tempname __P ((char *__buf, size_t __bufsize,
160 __const char *__dir,
161 __const char *__pfx,
162 int __dir_search,
163 size_t *__lenptr,
164 FILE **__streamptr));
167 /* Print out MESSAGE on the error output and abort. */
168 extern void __libc_fatal __P ((__const char *__message))
169 __attribute__ ((__noreturn__));
172 /* The FILE structure. */
173 struct __stdio_file
175 /* Magic number for validation. Must be negative in open streams
176 for the glue to Unix stdio getc/putc to work.
177 NOTE: stdio/glue.c has special knowledge of these first four members. */
178 int __magic;
179 #define _IOMAGIC 0xfedabeeb /* Magic number to fill `__magic'. */
180 #define _GLUEMAGIC 0xfeedbabe /* Magic for glued Unix streams. */
182 char *__bufp; /* Pointer into the buffer. */
183 char *__get_limit; /* Reading limit. */
184 char *__put_limit; /* Writing limit. */
186 char *__buffer; /* Base of buffer. */
187 size_t __bufsize; /* Size of the buffer. */
188 __ptr_t __cookie; /* Magic cookie. */
189 __io_mode __mode; /* File access mode. */
190 __io_functions __io_funcs; /* I/O functions. */
191 __room_functions __room_funcs;/* I/O buffer room functions. */
192 fpos_t __offset; /* Current file position. */
193 fpos_t __target; /* Target file position. */
194 FILE *__next; /* Next FILE in the linked list. */
195 char *__pushback_bufp; /* Old bufp if char pushed back. */
196 unsigned char __pushback; /* Pushed-back character. */
197 unsigned int __pushed_back:1; /* A char has been pushed back. */
198 unsigned int __eof:1; /* End of file encountered. */
199 unsigned int __error:1; /* Error encountered. */
200 unsigned int __userbuf:1; /* Buffer from user (should not be freed). */
201 unsigned int __linebuf:1; /* Flush on newline. */
202 unsigned int __linebuf_active:1; /* put_limit is not really in use. */
203 unsigned int __seen:1; /* This stream has been seen. */
204 unsigned int __ispipe:1; /* Nonzero if opened by popen. */
208 /* All macros used internally by other macros here and by stdio functions begin
209 with `__'. All of these may evaluate their arguments more than once. */
212 /* Nonzero if STREAM is a valid stream.
213 STREAM must be a modifiable lvalue (wow, I got to use that term).
214 See stdio/glue.c for what the confusing bit is about. */
215 #define __validfp(stream) \
216 (stream != NULL && \
217 ({ if (stream->__magic == _GLUEMAGIC) \
218 stream = *((struct { int __magic; FILE **__p; } *) stream)->__p; \
219 stream->__magic == _IOMAGIC; }))
221 /* Clear the error and EOF indicators of STREAM. */
222 #define __clearerr(stream) ((stream)->__error = (stream)->__eof = 0)
224 /* Nuke STREAM, making it unusable but available for reuse. */
225 extern void __invalidate __P ((FILE *__stream));
227 /* Make sure STREAM->__offset and STREAM->__target are initialized.
228 Returns 0 if successful, or EOF on
229 error (but doesn't set STREAM->__error). */
230 extern int __stdio_check_offset __P ((FILE *__stream));
233 /* The possibilities for the third argument to `setvbuf'. */
234 #define _IOFBF 0x1 /* Full buffering. */
235 #define _IOLBF 0x2 /* Line buffering. */
236 #define _IONBF 0x4 /* No buffering. */
239 /* Default buffer size. */
240 #define BUFSIZ 1024
243 /* End of file character.
244 Some things throughout the library rely on this being -1. */
245 #define EOF (-1)
248 /* The possibilities for the third argument to `fseek'.
249 These values should not be changed. */
250 #define SEEK_SET 0 /* Seek from beginning of file. */
251 #define SEEK_CUR 1 /* Seek from current position. */
252 #define SEEK_END 2 /* Seek from end of file. */
255 #ifdef __USE_SVID
256 /* Default path prefix for `tempnam' and `tmpnam'. */
257 #define P_tmpdir "/usr/tmp"
258 #endif
261 /* Get the values:
262 L_tmpnam How long an array of chars must be to be passed to `tmpnam'.
263 TMP_MAX The minimum number of unique filenames generated by tmpnam
264 (and tempnam when it uses tmpnam's name space),
265 or tempnam (the two are separate).
266 L_ctermid How long an array to pass to `ctermid'.
267 L_cuserid How long an array to pass to `cuserid'.
268 FOPEN_MAX Mininum number of files that can be open at once.
269 FILENAME_MAX Maximum length of a filename. */
270 #include <stdio_lim.h>
273 /* All the known streams are in a linked list
274 linked by the `next' field of the FILE structure. */
275 extern FILE *__stdio_head; /* Head of the list. */
277 /* Standard streams. */
278 extern FILE *stdin, *stdout, *stderr;
279 #ifdef __STRICT_ANSI__
280 /* ANSI says these are macros; satisfy pedants. */
281 #define stdin stdin
282 #define stdout stdout
283 #define stderr stderr
284 #endif
287 /* Remove file FILENAME. */
288 extern int remove __P ((__const char *__filename));
289 /* Rename file OLD to NEW. */
290 extern int rename __P ((__const char *__old, __const char *__new));
293 /* Create a temporary file and open it read/write. */
294 extern FILE *tmpfile __P ((void));
295 /* Generate a temporary filename. */
296 extern char *tmpnam __P ((char *__s));
298 #ifdef __USE_REENTRANT
299 /* This is the reentrant variant of `tmpnam'. The only difference is
300 that it does not allow S to be NULL. */
301 extern char *tmpnam_r __P ((char *__s));
302 #endif
305 #ifdef __USE_SVID
306 /* Generate a unique temporary filename using up to five characters of PFX
307 if it is not NULL. The directory to put this file in is searched for
308 as follows: First the environment variable "TMPDIR" is checked.
309 If it contains the name of a writable directory, that directory is used.
310 If not and if DIR is not NULL, that value is checked. If that fails,
311 P_tmpdir is tried and finally "/tmp". The storage for the filename
312 is allocated by `malloc'. */
313 extern char *tempnam __P ((__const char *__dir, __const char *__pfx));
314 #endif
317 /* This performs actual output when necessary, flushing
318 STREAM's buffer and optionally writing another character. */
319 extern int __flshfp __P ((FILE *__stream, int __c));
322 /* Close STREAM, or all streams if STREAM is NULL. */
323 extern int fclose __P ((FILE *__stream));
324 /* Flush STREAM, or all streams if STREAM is NULL. */
325 extern int fflush __P ((FILE *__stream));
328 /* Open a file and create a new stream for it. */
329 extern FILE *fopen __P ((__const char *__filename, __const char *__modes));
330 /* Open a file, replacing an existing stream with it. */
331 extern FILE *freopen __P ((__const char *__filename,
332 __const char *__modes, FILE *__stream));
334 /* Return a new, zeroed, stream.
335 You must set its cookie and io_mode.
336 The first operation will give it a buffer unless you do.
337 It will also give it the default functions unless you set the `seen' flag.
338 The offset is set to -1, meaning it will be determined by doing a
339 stationary seek. You can set it to avoid the initial tell call.
340 The target is set to -1, meaning it will be set to the offset
341 before the target is needed.
342 Returns NULL if a stream can't be created. */
343 extern FILE *__newstream __P ((void));
345 #ifdef __USE_POSIX
346 /* Create a new stream that refers to an existing system file descriptor. */
347 extern FILE *fdopen __P ((int __fd, __const char *__modes));
348 #endif
350 #ifdef __USE_GNU
351 /* Create a new stream that refers to the given magic cookie,
352 and uses the given functions for input and output. */
353 extern FILE *fopencookie __P ((__ptr_t __magic_cookie, __const char *__modes,
354 __io_functions __io_funcs));
356 /* Create a new stream that refers to a memory buffer. */
357 extern FILE *fmemopen __P ((__ptr_t __s, size_t __len, __const char *__modes));
359 /* Open a stream that writes into a malloc'd buffer that is expanded as
360 necessary. *BUFLOC and *SIZELOC are updated with the buffer's location
361 and the number of characters written on fflush or fclose. */
362 extern FILE *open_memstream __P ((char **__bufloc, size_t *__sizeloc));
363 #endif
366 /* If BUF is NULL, make STREAM unbuffered.
367 Else make it use buffer BUF, of size BUFSIZ. */
368 extern void setbuf __P ((FILE *__stream, char *__buf));
369 /* Make STREAM use buffering mode MODE.
370 If BUF is not NULL, use N bytes of it for buffering;
371 else allocate an internal buffer N bytes long. */
372 extern int setvbuf __P ((FILE *__stream, char *__buf,
373 int __modes, size_t __n));
375 #ifdef __USE_BSD
376 /* If BUF is NULL, make STREAM unbuffered.
377 Else make it use SIZE bytes of BUF for buffering. */
378 extern void setbuffer __P ((FILE *__stream, char *__buf, size_t __size));
380 /* Make STREAM line-buffered. */
381 extern void setlinebuf __P ((FILE *__stream));
382 #endif
385 /* Write formatted output to STREAM. */
386 extern int fprintf __P ((FILE *__stream, __const char *__format, ...));
387 /* Write formatted output to stdout. */
388 extern int printf __P ((__const char *__format, ...));
389 /* Write formatted output to S. */
390 extern int sprintf __P ((char *__s, __const char *__format, ...));
392 /* Write formatted output to S from argument list ARG. */
393 extern int vfprintf __P ((FILE *__s, __const char *__format,
394 __gnuc_va_list __arg));
395 /* Write formatted output to stdout from argument list ARG. */
396 extern int vprintf __P ((__const char *__format, __gnuc_va_list __arg));
397 /* Write formatted output to S from argument list ARG. */
398 extern int vsprintf __P ((char *__s, __const char *__format,
399 __gnuc_va_list __arg));
401 #ifdef __OPTIMIZE__
402 extern __inline int
403 vprintf (const char *__fmt, __gnuc_va_list __arg)
405 return vfprintf (stdout, __fmt, __arg);
407 #endif /* Optimizing. */
409 #ifdef __USE_GNU
410 /* Maximum chars of output to write in MAXLEN. */
411 extern int __snprintf __P ((char *__s, size_t __maxlen,
412 __const char *__format, ...));
413 extern int snprintf __P ((char *__s, size_t __maxlen,
414 __const char *__format, ...));
416 extern int __vsnprintf __P ((char *__s, size_t __maxlen,
417 __const char *__format, __gnuc_va_list __arg));
418 extern int vsnprintf __P ((char *__s, size_t __maxlen,
419 __const char *__format, __gnuc_va_list __arg));
421 /* Write formatted output to a string dynamically allocated with `malloc'.
422 Store the address of the string in *PTR. */
423 extern int vasprintf __P ((char **__ptr, __const char *__f,
424 __gnuc_va_list __arg));
425 extern int asprintf __P ((char **__ptr, __const char *__fmt, ...));
427 /* Write formatted output to a file descriptor. */
428 extern int vdprintf __P ((int __fd, __const char *__fmt,
429 __gnuc_va_list __arg));
430 extern int dprintf __P ((int __fd, __const char *__fmt, ...));
431 #endif
434 /* Read formatted input from STREAM. */
435 extern int fscanf __P ((FILE *__stream, __const char *__format, ...));
436 /* Read formatted input from stdin. */
437 extern int scanf __P ((__const char *__format, ...));
438 /* Read formatted input from S. */
439 extern int sscanf __P ((__const char *__s, __const char *__format, ...));
441 #ifdef __USE_GNU
442 /* Read formatted input from S into argument list ARG. */
443 extern int __vfscanf __P ((FILE *__s, __const char *__format,
444 __gnuc_va_list __arg));
445 extern int vfscanf __P ((FILE *__s, __const char *__format,
446 __gnuc_va_list __arg));
448 /* Read formatted input from stdin into argument list ARG. */
449 extern int __vscanf __P ((__const char *__format, __gnuc_va_list __arg));
450 extern int vscanf __P ((__const char *__format, __gnuc_va_list __arg));
452 /* Read formatted input from S into argument list ARG. */
453 extern int __vsscanf __P ((__const char *__s, __const char *__format,
454 __gnuc_va_list __arg));
455 extern int vsscanf __P ((__const char *__s, __const char *__format,
456 __gnuc_va_list __arg));
459 #ifdef __OPTIMIZE__
460 extern __inline int
461 vfscanf (FILE *__s, const char *__fmt, __gnuc_va_list __arg)
463 return __vfscanf (__s, __fmt, __arg);
465 extern __inline int
466 vscanf (const char *__fmt, __gnuc_va_list __arg)
468 return __vfscanf (stdin, __fmt, __arg);
470 extern __inline int
471 vsscanf (const char *__s, const char *__fmt, __gnuc_va_list __arg)
473 return __vsscanf (__s, __fmt, __arg);
475 #endif /* Optimizing. */
476 #endif /* Use GNU. */
479 /* This does actual reading when necessary, filling STREAM's
480 buffer and returning the first character in it. */
481 extern int __fillbf __P ((FILE *__stream));
484 /* Read a character from STREAM. */
485 extern int fgetc __P ((FILE *__stream));
486 extern int getc __P ((FILE *__stream));
488 /* Read a character from stdin. */
489 extern int getchar __P ((void));
491 /* The C standard explicitly says this can
492 re-evaluate its argument, so it does. */
493 #define __getc(stream) \
494 ((stream)->__bufp < (stream)->__get_limit ? \
495 (int) ((unsigned char) *(stream)->__bufp++) : __fillbf(stream))
497 /* The C standard explicitly says this is a macro,
498 so we always do the optimization for it. */
499 #define getc(stream) __getc(stream)
501 #ifdef __OPTIMIZE__
502 extern __inline int
503 getchar (void)
505 return __getc (stdin);
507 #endif /* Optimizing. */
510 /* Write a character to STREAM. */
511 extern int fputc __P ((int __c, FILE *__stream));
512 extern int putc __P ((int __c, FILE *__stream));
514 /* Write a character to stdout. */
515 extern int putchar __P ((int __c));
518 /* The C standard explicitly says this can
519 re-evaluate its arguments, so it does. */
520 #define __putc(c, stream) \
521 ((stream)->__bufp < (stream)->__put_limit ? \
522 (int) (unsigned char) (*(stream)->__bufp++ = (unsigned char) (c)) : \
523 __flshfp ((stream), (unsigned char) (c)))
525 /* The C standard explicitly says this can be a macro,
526 so we always do the optimization for it. */
527 #define putc(c, stream) __putc ((c), (stream))
529 #ifdef __OPTIMIZE__
530 extern __inline int
531 putchar (int __c)
533 return __putc (__c, stdout);
535 #endif
538 #if defined(__USE_SVID) || defined(__USE_MISC)
539 /* Get a word (int) from STREAM. */
540 extern int getw __P ((FILE *__stream));
542 /* Write a word (int) to STREAM. */
543 extern int putw __P ((int __w, FILE *__stream));
544 #endif
547 /* Get a newline-terminated string of finite length from STREAM. */
548 extern char *fgets __P ((char *__s, int __n, FILE *__stream));
550 /* Get a newline-terminated string from stdin, removing the newline.
551 DO NOT USE THIS FUNCTION!! There is no limit on how much it will read. */
552 extern char *gets __P ((char *__s));
555 #ifdef __USE_GNU
556 #include <sys/types.h>
558 /* Read up to (and including) a DELIMITER from STREAM into *LINEPTR
559 (and null-terminate it). *LINEPTR is a pointer returned from malloc (or
560 NULL), pointing to *N characters of space. It is realloc'd as
561 necessary. Returns the number of characters read (not including the
562 null terminator), or -1 on error or EOF. */
563 ssize_t __getdelim __P ((char **__lineptr, size_t *__n,
564 int __delimiter, FILE *__stream));
565 ssize_t getdelim __P ((char **__lineptr, size_t *__n,
566 int __delimiter, FILE *__stream));
568 /* Like `getdelim', but reads up to a newline. */
569 ssize_t __getline __P ((char **__lineptr, size_t *__n, FILE *__stream));
570 ssize_t getline __P ((char **__lineptr, size_t *__n, FILE *__stream));
572 #ifdef __OPTIMIZE__
573 extern __inline ssize_t
574 __getline (char **__lineptr, size_t *__n, FILE *__stream)
576 return __getdelim (__lineptr, __n, '\n', __stream);
579 extern __inline ssize_t
580 getdelim (char **__lineptr, size_t *__n, int __delimiter, FILE *__stream)
582 return __getdelim (__lineptr, __n, __delimiter, __stream);
584 extern __inline ssize_t
585 getline (char **__lineptr, size_t *__n, FILE *__stream)
587 return __getline (__lineptr, __n, __stream);
589 #endif /* Optimizing. */
590 #endif
593 /* Write a string to STREAM. */
594 extern int fputs __P ((__const char *__s, FILE *__stream));
595 /* Write a string, followed by a newline, to stdout. */
596 extern int puts __P ((__const char *__s));
599 /* Push a character back onto the input buffer of STREAM. */
600 extern int ungetc __P ((int __c, FILE *__stream));
603 /* Read chunks of generic data from STREAM. */
604 extern size_t fread __P ((__ptr_t __ptr, size_t __size,
605 size_t __n, FILE *__stream));
606 /* Write chunks of generic data to STREAM. */
607 extern size_t fwrite __P ((__const __ptr_t __ptr, size_t __size,
608 size_t __n, FILE *__s));
611 /* Seek to a certain position on STREAM. */
612 extern int fseek __P ((FILE *__stream, long int __off, int __whence));
613 /* Return the current position of STREAM. */
614 extern long int ftell __P ((FILE *__stream));
615 /* Rewind to the beginning of STREAM. */
616 extern void rewind __P ((FILE *__stream));
618 /* Get STREAM's position. */
619 extern int fgetpos __P ((FILE *__stream, fpos_t *__pos));
620 /* Set STREAM's position. */
621 extern int fsetpos __P ((FILE *__stream, __const fpos_t *__pos));
624 /* Clear the error and EOF indicators for STREAM. */
625 extern void clearerr __P ((FILE *__stream));
626 /* Return the EOF indicator for STREAM. */
627 extern int feof __P ((FILE *__stream));
628 /* Return the error indicator for STREAM. */
629 extern int ferror __P ((FILE *__stream));
631 #ifdef __OPTIMIZE__
632 #define feof(stream) ((stream)->__eof != 0)
633 #define ferror(stream) ((stream)->__error != 0)
634 #endif /* Optimizing. */
637 /* Print a message describing the meaning of the value of errno. */
638 extern void perror __P ((__const char *__s));
640 #ifdef __USE_BSD
641 extern int sys_nerr;
642 extern const char *const sys_errlist[];
643 #endif
644 #ifdef __USE_GNU
645 extern int _sys_nerr;
646 extern const char *const _sys_errlist[];
647 #endif
650 #ifdef __USE_POSIX
651 /* Return the system file descriptor for STREAM. */
652 extern int fileno __P ((FILE *__stream));
653 #endif /* Use POSIX. */
656 #if (defined (__USE_POSIX2) || defined(__USE_SVID) || defined(__USE_BSD) || \
657 defined(__USE_MISC))
658 /* Create a new stream connected to a pipe running the given command. */
659 extern FILE *popen __P ((__const char *__command, __const char *__modes));
661 /* Close a stream opened by popen and return the status of its child. */
662 extern int pclose __P ((FILE *__stream));
663 #endif
666 #ifdef __USE_POSIX
667 /* Return the name of the controlling terminal. */
668 extern char *ctermid __P ((char *__s));
669 /* Return the name of the current user. */
670 extern char *cuserid __P ((char *__s));
671 #endif
674 #ifdef __USE_GNU
675 struct obstack; /* See <obstack.h>. */
677 /* Open a stream that writes to OBSTACK. */
678 extern FILE *open_obstack_stream __P ((struct obstack *__obstack));
680 /* Write formatted output to an obstack. */
681 extern int obstack_printf __P ((struct obstack *__obstack,
682 __const char *__format, ...));
683 extern int obstack_vprintf __P ((struct obstack *__obstack,
684 __const char *__format,
685 __gnuc_va_list __args));
686 #endif
689 __END_DECLS
691 #endif /* <stdio.h> included. */
693 #endif /* stdio.h */