3 /* 7.19 Input/output <stdio.h>
5 This file is part of the Public Domain C Library (PDCLib).
6 Permission is granted to use, modify, and / or redistribute at will.
9 #ifndef _PDCLIB_STDIO_H
10 #define _PDCLIB_STDIO_H _PDCLIB_STDIO_H
13 #define _PDCLIB_INT_H _PDCLIB_INT_H
14 #include <_PDCLIB_int.h>
17 #ifndef _PDCLIB_SIZE_T_DEFINED
18 #define _PDCLIB_SIZE_T_DEFINED _PDCLIB_SIZE_T_DEFINED
19 typedef _PDCLIB_size_t size_t;
22 #ifndef _PDCLIB_NULL_DEFINED
23 #define _PDCLIB_NULL_DEFINED _PDCLIB_NULL_DEFINED
24 #define NULL _PDCLIB_NULL
27 /* See setvbuf(), third argument */
32 /* The following are platform-dependant, and defined in _PDCLIB_config.h. */
33 typedef struct _PDCLIB_fpos_t fpos_t;
34 typedef struct _PDCLIB_file_t FILE;
36 #define BUFSIZ _PDCLIB_BUFSIZ
37 #define FOPEN_MAX _PDCLIB_FOPEN_MAX
38 #define FILENAME_MAX _PDCLIB_FILENAME_MAX
39 #define L_tmpnam _PDCLIB_L_tmpnam
40 #define TMP_MAX _PDCLIB_TMP_MAX
42 /* See fseek(), third argument */
43 #define SEEK_CUR _PDCLIB_SEEK_CUR
44 #define SEEK_END _PDCLIB_SEEK_END
45 #define SEEK_SET _PDCLIB_SEEK_SET
51 /* Operations on files */
53 /* Remove the given file.
54 Returns zero if successful, non-zero otherwise.
55 This implementation does detect if a file of that name is currently open,
56 and fails the remove in this case. This does not detect two distinct names
57 that merely result in the same file (e.g. "/home/user/foo" vs. "~/foo").
59 int remove( const char * filename );
61 /* Rename the given old file to the given new name.
62 Returns zero if successful, non-zero otherwise.
63 This implementation does detect if the old filename corresponds to an open
64 file, and fails the rename in this case.
65 If there already is a file with the new filename, behaviour is defined by
66 the glue code (see functions/_PDCLIB/rename.c).
68 int rename( const char * old, const char * new );
70 /* Open a temporary file with mode "wb+", i.e. binary-update. Remove the file
71 automatically if it is closed or the program exits normally (by returning
72 from main() or calling exit()).
73 Returns a pointer to a FILE handle for this file.
74 This implementation does not remove temporary files if the process aborts
75 abnormally (e.g. abort()).
77 FILE * tmpfile( void );
79 /* Generate a file name that is not equal to any existing filename AT THE TIME
80 OF GENERATION. Generate a different name each time it is called.
81 Returns a pointer to an internal static buffer containing the filename if s
82 is a NULL pointer. (This is not thread-safe!)
83 Returns s if it is not a NULL pointer (s is then assumed to point to an array
84 of at least L_tmpnam characters).
85 Returns NULL if unable to generate a suitable name (because all possible
86 names already exist, or the function has been called TMP_MAX times already).
87 Note that this implementation cannot guarantee a file of the name generated
88 is not generated between the call to this function and a subsequent fopen().
90 char * tmpnam( char * s );
92 /* File access functions */
94 /* Close the file associated with the given stream (after flushing its buffers).
95 Returns zero if successful, EOF if any errors occur.
97 int fclose( FILE * stream );
99 /* Flush the buffers of the given output stream. If the stream is an input
100 stream, or an update stream with the last operation being an input operation,
101 behaviour is undefined.
102 If stream is a NULL pointer, perform the buffer flushing for all applicable
104 Returns zero if successful, EOF if a write error occurs.
105 Sets the error indicator of the stream if a write error occurs.
107 int fflush( FILE * stream );
109 /* Open the file with the given filename in the given mode, and return a stream
110 handle for it in which error and end-of-file indicator are cleared. Defined
114 text files binary files
115 without update "r" "rb"
116 with update "r+" "rb+" or "r+b"
118 Opening in read mode fails if no file with the given filename exists, or if
122 text files binary files
123 without update "w" "wb"
124 with update "w+" "wb+" or "w+b"
126 With write modes, if a file with the given filename already exists, it is
127 truncated to zero length.
130 text files binary files
131 without update "a" "ab"
132 with update "a+" "ab+" or "a+b"
134 With update modes, if a file with the given filename already exists, it is
135 not truncated to zero length, but all writes are forced to end-of-file (this
136 regardless to fseek() calls). Note that binary files opened in append mode
137 might have their end-of-file padded with '\0' characters.
139 Update modes mean that both input and output functions can be performed on
140 the stream, but output must be terminated with a call to either fflush(),
141 fseek(), fsetpos(), or rewind() before input is performed, and input must
142 be terminated with a call to either fseek(), fsetpos(), or rewind() before
143 output is performed, unless input encountered end-of-file.
145 If a text file is opened with update mode, the implementation is at liberty
146 to open a binary stream instead. This implementation honors the exact mode
149 The stream is fully buffered if and only if it can be determined not to
150 refer to an interactive device.
152 If the mode string begins with but is longer than one of the above sequences
153 the implementation is at liberty to ignore the additional characters, or do
154 implementation-defined things. This implementation only accepts the exact
157 Returns a pointer to the stream handle if successfull, NULL otherwise.
159 FILE * fopen( const char * _PDCLIB_restrict filename, const char * _PDCLIB_restrict mode );
161 /* Close any file currently associated with the given stream. Open the file
162 identified by the given filename with the given mode (equivalent to fopen()),
163 and associate it with the given stream. If filename is a NULL pointer,
164 attempt to change the mode of the given stream.
165 This implementation allows any mode changes on "real" files, and associating
166 of the standard streams with files. It does *not* support mode changes on
168 (Primary use of this function is to redirect stdin, stdout, and stderr.)
170 FILE * freopen( const char * _PDCLIB_restrict filename, const char * _PDCLIB_restrict mode, FILE * _PDCLIB_restrict stream );
172 /* If buf is a NULL pointer, call setvbuf( stream, NULL, _IONBF, BUFSIZ ).
173 If buf is not a NULL pointer, call setvbuf( stream, buf, _IOFBF, BUFSIZ ).
175 void setbuf( FILE * _PDCLIB_restrict stream, char * _PDCLIB_restrict buf );
177 /* Set the given stream to the given buffering mode. If buf is not a NULL
178 pointer, use buf as file buffer (of given size). If buf is a NULL pointer,
179 use a buffer of given size allocated internally. _IONBF causes unbuffered
180 behaviour, _IOLBF causes line-buffered behaviour, _IOFBF causes fully
181 buffered behaviour. Calling this function is only valid right after a file is
182 opened, and before any other operation (except for any unsuccessful calls to
183 setvbuf()) has been performed.
184 Returns zero if successful, nonzero otherwise.
186 int setvbuf( FILE * _PDCLIB_restrict stream, char * _PDCLIB_restrict buf, int mode, size_t size );
188 /* Formatted input/output functions */
191 Write output to the given stream, as defined by the given format string and
192 0..n subsequent arguments (the argument stack).
194 The format string is written to the given stream verbatim, except for any
195 conversion specifiers included, which start with the letter '%' and are
196 documented below. If the given conversion specifiers require more arguments
197 from the argument stack than provided, behaviour is undefined. Additional
198 arguments not required by conversion specifiers are evaluated but otherwise
201 (The standard specifies the format string is allowed to contain multibyte
202 character sequences as long as it starts and ends in initial shift state,
203 but this is not yet supported by this implementation, which interprets the
204 format string as sequence of char.)
205 TODO: Add multibyte support to printf() functions.
207 A conversion specifier consists of:
208 - Zero or more flags (one of the characters "-+ #0").
209 - Optional minimum field width as decimal integer. Default is padding to the
210 left, using spaces. Note that 0 is taken as a flag, not the beginning of a
211 field width. Note also that a small field width will not result in the
212 truncation of a value.
213 - Optional precision (given as ".#" with # being a decimal integer),
215 - the min. number of digits to appear (diouxX),
216 - the max. number of digits after the decimal point (aAeEfF),
217 - the max. number of significant digits (gG),
218 - the max. number of bytes to be written (s).
219 - behaviour with other conversion specifiers is undefined.
220 - Optional length modifier specifying the size of the argument (one of "hh",
221 "ll", or one of the characters "hljztL").
222 - Conversion specifier character specifying the type of conversion to be
223 applied (and the type of the next argument from the argument stack). One
224 of the characters "diouxXfFeEgGaAcspn%".
226 Minimum field width and/or precision may be given as asterisk ('*') instead
227 of a decimal integer. In this case, the next argument from the argument
228 stack is assumed to be an int value specifying the width / precision. A
229 negative field width is interpreted as flag '-' followed by a positive field
230 width. A negative precision is interpreted as if no precision was given.
233 - Left-justify the conversion result within its field width.
234 + Prefix a '+' on positive signed conversion results. Prefix a '-' on
235 floating conversions resulting in negative zero, or negative values
237 space Prefix a space on positive signed conversion results, or if a signed
238 conversion results in no characters. If both '+' and ' ' are given,
240 # Use an "alternative form" for
241 - 'o' conversion, increasing precision until the first digit of the
243 - 'x' or 'X' conversion, prefixing "0x" or "0X" to nonzero results;
244 - "aAeEfF" conversions, always printing a decimal point even if no
245 digits are following;
246 - 'g' or 'G' conversions, always printing a decimal point even if no
247 digits are following, and not removing trailing zeroes.
248 - behaviour for other conversions is unspecified.
249 0 Use leading zeroes instead of spaces for field width padding. If both
250 '-' and '0' are given, '0' is ignored. If a precision is specified for
251 any of the "diouxX" conversions, '0' is ignored. Behaviour is only
252 defined for "diouxXaAeEfFgG".
255 hh For "diouxX" conversions, the argument from the argument stack is
256 assumed to be of char width. (It will have been subject to integer
257 promotion but will be converted back.) For 'n' conversions, the argument
258 is assumed to be a pointer to signed char.
259 h For "diouxX" conversions, the argument from the argument stack is
260 assumed to be of short int width. (It will have been subject to integer
261 promotion but will be converted back.) For 'n' conversions, the argument
262 is assumed to be a pointer to short int.
263 l For "diouxX" conversions, the argument from the argument stack is
264 assumed to be of long int width. For 'n' conversions, the argument is
265 assumed to be a pointer to short int. For 'c' conversions, the argument
266 is assumed to be a wint_t. For 's' conversions, the argument is assumed
267 to be a pointer to wchar_t. No effect on "aAeEfFgG" conversions.
268 ll For "diouxX" conversions, the argument from the argument stack is
269 assumed to be of long long int width. For 'n' conversions, the argument
270 is assumed to be a pointer to long long int.
271 j For "diouxX" conversions, the argument from the argument stack is
272 assumed to be of intmax_t width. For 'n' conversions, the argument is
273 assumed to be a pointer to intmax_t.
274 z For "diouxX" conversions, the argument from the argument stack is
275 assumed to be of size_t width. For 'n' conversions, the argument is
276 assumed to be a pointer to size_t.
277 t For "diouxX" conversions, the argument from the argument stack is
278 assumed to be of ptrdiff_t width. For 'n' conversions, the argument is
279 assumed to be a pointer to ptrdiff_t.
280 L For "aAeEfFgG" conversions, the argument from the argument stack is
281 assumed to be a long double.
282 Length modifiers appearing for any conversions not mentioned above will have
284 If a length modifier appears with any conversion specifier other than as
285 specified above, the behavior is undefined.
287 CONVERSION SPECIFIERS
288 d,i The argument from the argument stack is assumed to be of type int, and
289 is converted to a signed decimal value with a minimum number of digits
290 as specified by the precision (default 1), padded with leading zeroes.
291 A zero value converted with precision zero yields no output.
292 o The argument from the argument stack is assumed to be of type unsigned
293 int, and is converted to an unsigned octal value, other behaviour being
295 u The argument from the argument stack is assumed to be of type unsigned
296 int, and converted to an unsigned decimal value, other behaviour being
298 x,X The argument from the argument stack is assumed to be of type unsigned
299 int, and converted to an unsigned hexadecimal value, using lowercase
300 "abcdef" for 'x' and uppercase "ABCDEF" for 'X' conversion, other
301 behaviour being as above.
302 f,F The argument from the argument stack is assumed to be of type double,
303 and converted to a decimal floating point in decimal-point notation,
304 with the number of digits after the decimal point as specified by the
305 precision (default 6) and the value being rounded appropriately. If
306 precision is zero (and the '#' flag is not given), no decimal point is
307 printed. At least one digit is always printed before the decimal point.
308 For 'f' conversions, an infinity value is printed as either [-]inf or
309 [-]infinity (, depending on the configuration of this implementation. A
310 NaN value is printed as [-]nan. For 'F' conversions uppercase characters
311 are used for these special values. The flags '-', '+' and ' ' apply as
312 usual to these special values, '#' and '0' have no effect.
313 e,E The argument from the argument stack is assumed to be of type double,
314 and converted to a decimal floating point in normalized exponential
315 notation ([?]d.ddd edd). "Normalized" means one nonzero digit before
316 the decimal point, unless the value is zero. The number of digits after
317 the decimal point is specified by the precision (default 6), the value
318 being rounded appropriately. If precision is zero (and the '#' flag is
319 not given), no decimal point is printed. The exponent has at least two
320 digits, and not more than necessary to represent the exponent. If the
321 value is zero, the exponent is zero. The 'e' written to indicate the
322 exponend is uppercase for 'E' conversions.
323 Infinity or NaN values are represented as for 'f' and 'F' conversions,
325 g,G The argument from the argument stack is assumed to be of type double,
326 and converted according to either 'f' or 'e' format for 'g' conversions,
327 or 'F' or 'E' format for 'G' conversions, respectively, with the actual
328 conversion chosen depending on the value. 'e' / 'E' conversion is chosen
329 if the resulting exponent is < -4 or >= the precision (default 1).
330 Trailing zeroes are removed (unless the '#' flag is given). A decimal
331 point appears only if followed by a digit.
332 Infinity or NaN values are represented as for 'f' and 'F' conversions,
334 a,A The argument from the argument stack is assumed to be of type double,
335 and converted to a floating point hexadecimal notation ([?]0xh.hhhh pd)
336 with one hexadecimal digit (being nonzero if the value is normalized,
337 and otherwise unspecified) before the decimal point, and the number of
338 digits after the decimal point being specified by the precision. If no
339 precision is given, the default is to print as many digits as nevessary
340 to give an exact representation of the value (if FLT_RADIX is a power of
341 2). If no precision is given and FLT_RADIX is not a power of 2, the
342 default is to print as many digits to distinguish values of type double
343 (possibly omitting trailing zeroes). (A precision p is sufficient to
344 distinguish values of the source type if 16^p-1 > b^n where b is
345 FLT_RADIX and n is the number of digits in the significand (to base b)
346 of the source type. A smaller p might suffice depending on the
347 implementation's scheme for determining the digit to the left of the
348 decimal point.) The error has the correct sign for the current rounding
350 Unless the '#' flag is given, no decimal-point is given for zero
352 The 'a' conversion uses lowercase "abcdef", "0x" and 'p', the 'A'
353 conversion uppercase "ABCDEF", "0X" and 'P'.
354 The exponent always has at least one digit, and not more than necessary
355 to represent the decimal exponent of 2. If the value is zero, the
357 Infinity or NaN values are represented as for 'f' and 'F' conversions,
359 Binary implementations are at liberty to chose the hexadecimal digit to
360 the left of the decimal point so that subsequent digits align to nibble
362 c The argument from the argument stack is assumed to be of type int, and
363 converted to a character after the value has been cast to unsigned char.
364 If the 'l' length modifier is given, the argument is assumed to be of
365 type wint_t, and converted as by a "%ls" conversion with no precision
366 and a pointer to a two-element wchar_t array, with the first element
367 being the wint_t argument and the second a '\0' wide character.
368 s The argument from the argument stack is assumed to be a char array (i.e.
369 pointer to char). Characters from that array are printed until a zero
370 byte is encountered or as many bytes as specified by a given precision
372 If the l length modifier is given, the argument from the argument stack
373 is assumed to be a wchar_t array (i.e. pointer to wchar_t). Wide
374 characters from that array are converted to multibyte characters as by
375 calls to wcrtomb() (using a mbstate_t object initialized to zero prior
376 to the first conversion), up to and including the terminating null wide
377 character. The resulting multibyte character sequence is then printed up
378 to but not including the terminating null character. If a precision is
379 given, it specifies the maximum number of bytes to be written (including
380 shift sequences). If the given precision would require access to a wide
381 character one past the end of the array, the array shall contain a '\0'
382 wide character. In no case is a partial multibyte character written.
383 Redundant shift sequences may result if the multibyte characters have a
384 state-dependent encoding.
385 TODO: Clarify these statements regarding %ls.
386 p The argument from the argument stack is assumed to be a void pointer,
387 and converted to a sequence of printing characters in an implementation-
389 This implementation casts the pointer to type intptr_t, and prints the
390 value as if a %#x conversion specifier was given.
391 n The argument from the argument stack is assumed to be a pointer to a
392 signed integer, into which the number of characters written so far by
393 this call to fprintf is stored. The behaviour, should any flags, field
394 widths, or precisions be given is undefined.
395 % A verbatim '%' character is written. No argument is taken from the
398 Returns the number of characters written if successful, a negative value
401 int fprintf( FILE * _PDCLIB_restrict stream, const char * _PDCLIB_restrict format, ... );
403 /* TODO: fscanf() documentation */
405 Read input from a given stream, as defined by the given format string, and
406 store converted input in the objects pointed to by 0..n subsequent arguments
407 (the argument stack).
409 The format string contains a sequence of directives that are expected to
410 match the input. If such a directive fails to match, the function returns
411 (matching error). It also returns if an input error occurs (input error).
414 - one or more whitespaces, matching any number of whitespaces in the input;
415 - printing characters, matching the input verbatim;
416 - conversion specifications, which convert an input sequence into a value as
417 defined by the individual specifier, and store that value in a memory
418 location pointed to by the next pointer on the argument stack. Details are
419 documented below. If there is an insufficient number of pointers on the
420 argument stack, behaviour is undefined. Additional arguments not required
421 by any conversion specifications are evaluated, but otherwise ignored.
423 (The standard specifies the format string is allowed to contain multibyte
424 character sequences as long as it starts and ends in initial shift state,
425 but this is not yet supported by this implementation, which interprets the
426 format string as sequence of char.)
427 TODO: Add multibyte support to scanf() functions.
429 A conversion specifier consists of:
430 - Optional assignment-suppressing character ('*') that makes the conversion
431 read input as usual, but does not assign the conversion result.
432 - Optional maximum field width as decimal integer.
433 - Optional length modifier specifying the size of the argument (one of "hh",
434 "ll", or one of the characters "hljztL").
435 - Conversion specifier character specifying the type of conversion to be
436 applied (and the type of the next argument from the argument stack). One
437 of the characters "diouxXaAeEfFgGcs[pn%".
440 hh For "diouxXn" conversions, the next pointer from the argument stack is
441 assumed to point to a variable of of char width.
442 h For "diouxXn" conversions, the next pointer from the argument stack is
443 assumed to point to a variable of short int width.
444 l For "diouxXn" conversions, the next pointer from the argument stack is
445 assumed to point to a variable of long int width.
446 For "aAeEfFgG" conversions, it is assumed to point to a variable of type
448 For "cs[" conversions, it is assumed to point to a variable of type
450 ll For "diouxXn" conversions, the next pointer from the argument stack is
451 assumed to point to a variable of long long int width.
452 j For "diouxXn" conversions, the next pointer from the argument stack is
453 assumed to point to a variable of intmax_t width.
454 z For "diouxXn" conversions, the next pointer from the argument stack is
455 assumed to point to a variable of size_t width.
456 t For "diouxXn" conversions, the next pointer from the argument stack is
457 assumed to point to a variable of ptrdiff_t width.
458 L For "aAeEfFgG" conversions, the next pointer from the argument stack is
459 assumed to point to a variable of type long double.
460 Length modifiers appearing for any conversions not mentioned above will have
462 If a length modifier appears with any conversion specifier other than as
463 specified above, the behavior is undefined.
465 CONVERSION SPECIFIERS
466 d Matches an (optionally signed) decimal integer of the format expected
467 by strtol() with base 10. The next pointer from the argument stack is
468 assumed to point to a signed integer.
469 i Matches an (optionally signed) integer of the format expected by
470 strtol() with base 0. The next pointer from the argument stack is
471 assumed to point to a signed integer.
472 o Matches an (optionally signed) octal integer of the format expected by
473 strtoul() with base 8. The next pointer from the argument stack is
474 assumed to point to an unsigned integer.
475 u Matches an (optionally signed) decimal integer of the format expected
476 by strtoul() with base 10. The next pointer from the argument stack is
477 assumed to point to an unsigned integer.
478 x Matches an (optionally signed) hexadecimal integer of the format
479 expected by strtoul() with base 16. The next pointer from the argument
480 stack is assumed to point to an unsigned integer.
481 aefg Matches an (optionally signed) floating point number, infinity, or not-
482 a-number-value of the format expected by strtod(). The next pointer
483 from the argument stack is assumed to point to a float.
484 c Matches a number of characters as specified by the field width (default
485 1). The next pointer from the argument stack is assumed to point to a
486 character array large enough to hold that many characters.
487 If the 'l' length modifier is given, the input is assumed to match a
488 sequence of multibyte characters (starting in the initial shift state),
489 which will be converted to a wide character sequence as by successive
490 calls to mbrtowc() with a mbstate_t object initialized to zero prior to
491 the first conversion. The next pointer from the argument stack is
492 assumed to point to a wchar_t array large enough to hold that many
494 In either case, note that no '\0' character is added to terminate the
496 s Matches a sequence of non-white-space characters. The next pointer from
497 the argument stack is assumed to point to a character array large
498 enough to hold the sequence including terminating '\0' character.
499 If the 'l' length modifier is given, the input is assumed to match a
500 sequence of multibyte characters (starting in the initial shift state),
501 which will be converted to a wide character sequence as by a call to
502 mbrtowc() with a mbstate_t object initialized to zero prior to the
503 first conversion. The next pointer from the argument stack is assumed
504 to point to a wchar_t array large enough to hold the sequence including
505 terminating '\0' character.
506 [ Matches a nonempty sequence consisting of any of those characters
507 specified between itself and a corresponding closing bracket (']').
508 If the first character in the list is a circumflex ('^'), this matches
509 a nonempty sequence consisting of any characters NOT specified. If the
510 closing bracket appears as the first character in the scanset ("[]" or
511 "[^]", it is assumed to belong to the scanset, which then ends with the
512 NEXT closing bracket.
513 If there is a '-' character in the scanset which is not the first after
514 the opening bracket (or the circumflex, see above) or the last in the
515 scanset, behaviour is implementation-defined. This implementation
516 handles this character like any other.
518 The extend of the input field is determined byte-by-byte for the above
519 conversions ('c', 's', '['), with no special provisions being made for
520 multibyte characters. The resulting field is nevertheless a multibyte
521 sequence begining in intial shift state.
523 p Matches a sequence of characters as produced by the printf() "%p"
524 conversion. The next pointer from the argument stack is assumed to
525 point to a void pointer, which will be filled with the same location
526 as the pointer used in the printf() statement. Note that behaviour is
527 undefined if the input value is not the result of an earlier printf()
529 n Does not read input. The next pointer from the argument stack is
530 assumed to point to a signed integer, into which the number of
531 characters read from input so far by this call to fscanf() is stored.
532 This does not affect the return value of fscanf(). The behaviour,
533 should an assignment-supressing character of field width be given,
535 This can be used to test the success of literal matches and suppressed
537 % Matches a single, verbatim '%' character.
539 A, E, F, G and X are valid, and equivalent to their lowercase counterparts.
541 All conversions except [, c, or n imply that whitespace characters from the
542 input stream are consumed until a non-whitespace character is encountered.
543 Such whitespaces do not count against a maximum field width.
545 Conversions push at most one character back into the input stream. That
546 implies that some character sequences converted by the strtol() and strtod()
547 function families are not converted identically by the scnaf() function
550 Returns the number of input items successfully assigned. This can be zero if
551 an early mismatch occurs. Returns EOF if an input failure occurs before the
554 int fscanf( FILE * _PDCLIB_restrict stream, const char * _PDCLIB_restrict format, ... );
556 /* Equivalent to fprintf( stdout, format, ... ). */
557 int printf( const char * _PDCLIB_restrict format, ... );
559 /* Equivalent to fscanf( stdin, format, ... ). */
560 int scanf( const char * _PDCLIB_restrict format, ... );
562 /* Equivalent to fprintf( stdout, format, ... ), except that the result is
563 written into the buffer pointed to by s, instead of stdout, and that any
564 characters beyond the (n-1)th are discarded. The (n)th character is
565 replaced by a '\0' character in this case.
566 Returns the number of characters that would have been written (not counting
567 the terminating '\0' character) if n had been sufficiently large, if
568 successful, and a negative number if an encoding error ocurred.
570 int snprintf( char * _PDCLIB_restrict s, size_t n, const char * _PDCLIB_restrict format, ... );
572 /* Equivalent to fprintf( stdout, format, ... ), except that the result is
573 written into the buffer pointed to by s, instead of stdout.
575 int sprintf( char * _PDCLIB_restrict s, const char * _PDCLIB_restrict format, ... );
577 /* Equivalent to fscanf( stdin, format, ... ), except that the input is read
578 from the buffer pointed to by s, instead of stdin.
580 int sscanf( const char * _PDCLIB_restrict s, const char * _PDCLIB_restrict format, ... );
582 /* Equivalent to fprintf( stream, format, ... ), except that the argument stack
583 is passed as va_list parameter. Note that va_list is not declared by
586 int vfprintf( FILE * _PDCLIB_restrict stream, const char * _PDCLIB_restrict format, _PDCLIB_va_list arg );
588 /* Equivalent to fscanf( stream, format, ... ), except that the argument stack
589 is passed as va_list parameter. Note that va_list is not declared by
592 int vfscanf( FILE * _PDCLIB_restrict stream, const char * _PDCLIB_restrict format, _PDCLIB_va_list arg );
594 /* Equivalent to fprintf( stdout, format, ... ), except that the argument stack
595 is passed as va_list parameter. Note that va_list is not declared by
598 int vprintf( const char * _PDCLIB_restrict format, _PDCLIB_va_list arg );
600 /* Equivalent to fscanf( stdin, format, ... ), except that the argument stack
601 is passed as va_list parameter. Note that va_list is not declared by
604 int vscanf( const char * _PDCLIB_restrict format, _PDCLIB_va_list arg );
606 /* Equivalent to snprintf( s, n, format, ... ), except that the argument stack
607 is passed as va_list parameter. Note that va_list is not declared by
610 int vsnprintf( char * _PDCLIB_restrict s, size_t n, const char * _PDCLIB_restrict format, _PDCLIB_va_list arg );
612 /* Equivalent to fprintf( stdout, format, ... ), except that the argument stack
613 is passed as va_list parameter, and the result is written to the buffer
614 pointed to by s, instead of stdout. Note that va_list is not declared by
617 int vsprintf( char * _PDCLIB_restrict s, const char * _PDCLIB_restrict format, _PDCLIB_va_list arg );
619 /* Equivalent to fscanf( stdin, format, ... ), except that the argument stack
620 is passed as va_list parameter, and the input is read from the buffer
621 pointed to by s, instead of stdin. Note that va_list is not declared by
624 int vsscanf( const char * _PDCLIB_restrict s, const char * _PDCLIB_restrict format, _PDCLIB_va_list arg );
626 /* Character input/output functions */
628 /* Retrieve the next character from given stream.
629 Returns the character, EOF otherwise.
630 If end-of-file is reached, the EOF indicator of the stream is set.
631 If a read error occurs, the error indicator of the stream is set.
633 int fgetc( FILE * stream );
635 /* Read at most n-1 characters from given stream into the array s, stopping at
636 \n or EOF. Terminate the read string with \n. If EOF is encountered before
637 any characters are read, leave the contents of s unchanged.
638 Returns s if successful, NULL otherwise.
639 If a read error occurs, the error indicator of the stream is set. In this
640 case, the contents of s are indeterminate.
642 char * fgets( char * _PDCLIB_restrict s, int n, FILE * _PDCLIB_restrict stream );
644 /* Write the value c (cast to unsigned char) to the given stream.
645 Returns c if successful, EOF otherwise.
646 If a write error occurs, sets the error indicator of the stream is set.
648 int fputc( int c, FILE * stream );
650 /* Write the string s (not including the terminating \0) to the given stream.
651 Returns a value >=0 if successful, EOF otherwise.
652 This implementation does set the error indicator of the stream if a write
655 int fputs( const char * _PDCLIB_restrict s, FILE * _PDCLIB_restrict stream );
657 /* Equivalent to fgetc( stream ), but may be implemented as a macro that
658 evaluates its parameter more than once.
660 #define getc( stream ) fgetc( stream )
662 /* Equivalent to fgetc( stdin ), but may be implemented as a macro. */
663 #define getchar() fgetc( stdin )
665 /* Read characters from given stream into the array s, stopping at \n or EOF.
666 The string read is terminated with \0. Returns s if successful. If EOF is
667 encountered before any characters are read, the contents of s are unchanged,
668 and NULL is returned. If a read error occurs, the contents of s are indeter-
669 minate, and NULL is returned.
671 char * gets( char * s );
673 /* Equivalent to fputc( c, stream ), but may be implemented as a macro that
674 evaluates its parameter more than once.
676 #define putc( c, stream ) fputc( c, stream )
678 /* Equivalent to fputc( c, stdout ), but may be implemented as a macro that
679 evaluates its parameter more than once.
681 #define putchar( c ) putc( c, stdout )
683 /* Write the string s (not including the terminating \0) to stdout, and append
684 a newline to the output. Returns a value >= 0 when successful, EOF if a
685 write error occurred.
687 int puts( const char * s );
689 /* Push the value c (cast to unsigned char) back onto the given (input) stream.
690 A character pushed back in this way will be delivered by subsequent read
691 operations (and skipped by subsequent file positioning operations) as if it
692 has not been read. The external representation of the stream is unaffected
693 by this pushback (it is a buffer operation). One character of pushback is
694 guaranteed, further pushbacks may fail. EOF as value for c does not change
695 the input stream and results in failure of the function.
696 For text files, the file position indicator is indeterminate until all
697 pushed-back characters are read. For binary files, the file position
698 indicator is decremented by each successful call of ungetc(). If the file
699 position indicator for a binary file was zero before the call of ungetc(),
700 behaviour is undefined. (Older versions of the library allowed such a call.)
701 Returns the pushed-back character if successful, EOF if it fails.
703 int ungetc( int c, FILE * stream );
705 /* Direct input/output functions */
707 /* Read up to nmemb elements of given size from given stream into the buffer
708 pointed to by ptr. Returns the number of elements successfully read, which
709 may be less than nmemb if a read error or EOF is encountered. If a read
710 error is encountered, the value of the file position indicator is
711 indeterminate. If a partial element is read, its value is indeterminate.
712 If size or nmemb are zero, the function does nothing and returns zero.
714 size_t fread( void * _PDCLIB_restrict ptr, size_t size, size_t nmemb, FILE * _PDCLIB_restrict stream );
716 /* Write up to nmemb elements of given size from buffer pointed to by ptr to
717 the given stream. Returns the number of elements successfully written, which
718 will be less than nmemb only if a write error is encountered. If a write
719 error is encountered, the value of the file position indicator is
720 indeterminate. If size or nmemb are zero, the function does nothing and
723 size_t fwrite( const void * _PDCLIB_restrict ptr, size_t size, size_t nmemb, FILE * _PDCLIB_restrict stream );
725 /* File positioning functions */
727 /* Store the current position indicator (and, where appropriate, the current
728 mbstate_t status object) for the given stream into the given pos object. The
729 actual contents of the object are unspecified, but it can be used as second
730 parameter to fsetpos() to reposition the stream to the exact position and
731 parse state at the time fgetpos() was called.
732 Returns zero if successful, nonzero otherwise.
733 TODO: Implementation-defined errno setting for fgetpos().
735 int fgetpos( FILE * _PDCLIB_restrict stream, fpos_t * _PDCLIB_restrict pos );
737 /* Set the position indicator for the given stream to the given offset from:
738 - the beginning of the file if whence is SEEK_SET,
739 - the current value of the position indicator if whence is SEEK_CUR,
740 - end-of-file if whence is SEEK_END.
741 On text streams, non-zero offsets are only allowed with SEEK_SET, and must
742 have been returned by ftell() for the same file.
743 Any characters buffered by ungetc() are dropped, the end-of-file indicator
744 for the stream is cleared. If the given stream is an update stream, the next
745 operation after a successful fseek() may be either input or output.
746 Returns zero if successful, nonzero otherwise. If a read/write error occurs,
747 the error indicator for the given stream is set.
749 int fseek( FILE * stream, long int offset, int whence );
751 /* Set the position indicator (and, where appropriate the mbstate_t status
752 object) for the given stream to the given pos object (created by an earlier
753 call to fgetpos() on the same file).
754 Any characters buffered by ungetc() are dropped, the end-of-file indicator
755 for the stream is cleared. If the given stream is an update stream, the next
756 operation after a successful fsetpos() may be either input or output.
757 Returns zero if successful, nonzero otherwise. If a read/write error occurs,
758 the error indicator for the given stream is set.
759 TODO: Implementation-defined errno setting for fsetpos().
761 int fsetpos( FILE * stream, const fpos_t * pos );
763 /* Return the current offset of the given stream from the beginning of the
764 associated file. For text streams, the exact value returned is unspecified
765 (and may not be equal to the number of characters), but may be used in
766 subsequent calls to fseek().
767 Returns -1L if unsuccessful.
768 TODO: Implementation-defined errno setting for ftell().
770 long int ftell( FILE * stream );
772 /* Equivalent to (void)fseek( stream, 0L, SEEK_SET ), except that the error
773 indicator for the stream is also cleared.
775 void rewind( FILE * stream );
777 /* Error-handling functions */
779 /* Clear the end-of-file and error indicators for the given stream. */
780 void clearerr( FILE * stream );
782 /* Return zero if the end-of-file indicator for the given stream is not set,
785 int feof( FILE * stream );
787 /* Return zero if the error indicator for the given stream is not set, nonzero
790 int ferror( FILE * stream );
792 /* If s is neither a NULL pointer nor an empty string, print the string to
793 stderr (with appended colon (':') and a space) first. In any case, print an
794 error message depending on the current value of errno (being the same as if
795 strerror( errno ) had been called).
797 void perror( const char * s );