stdlib/stdlib.h

   1 /* Copyright (C) 1991,92,93,94,95,96,97,98 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   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.
   8
   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.
  13
  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 not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 /*
  20  *      ISO S Standard: 4.10 GENERAL UTILITIES  <stdlib.h>
  21  */
  22
  23 #ifndef _STDLIB_H
  24
  25 #define _STDLIB_H       1
  26 #include <features.h>
  27
  28 /* Get size_t, wchar_t and NULL from <stddef.h>.  */
  29 #define __need_size_t
  30 #define __need_wchar_t
  31 #define __need_NULL
  32 #include <stddef.h>
  33
  34 __BEGIN_DECLS
  35
  36 /* Returned by `div'.  */
  37 typedef struct
  38   {
  39     int quot;                   /* Quotient.  */
  40     int rem;                    /* Remainder.  */
  41   } div_t;
  42
  43 /* Returned by `ldiv'.  */
  44 typedef struct
  45   {
  46     long int quot;              /* Quotient.  */
  47     long int rem;               /* Remainder.  */
  48   } ldiv_t;
  49
  50 #ifdef __USE_GNU
  51 /* Returned by `lldiv'.  */
  52 typedef struct
  53   {
  54     long long int quot;         /* Quotient.  */
  55     long long int rem;          /* Remainder.  */
  56   } lldiv_t;
  57 #endif
  58
  59
  60 /* The largest number rand will return (same as INT_MAX).  */
  61 #define RAND_MAX        2147483647
  62
  63
  64 /* We define these the same for all machines.
  65    Changes from this to the outside world should be done in `_exit'.  */
  66 #define EXIT_FAILURE    1       /* Failing exit status.  */
  67 #define EXIT_SUCCESS    0       /* Successful exit status.  */
  68
  69
  70 /* Maximum length of a multibyte character in the current locale.  */
  71 #define MB_CUR_MAX      (__ctype_get_mb_cur_max ())
  72 extern int __ctype_get_mb_cur_max __P ((void));
  73
  74
  75 /* Convert a string to a floating-point number.  */
  76 extern double atof __P ((__const char *__nptr));
  77 /* Convert a string to an integer.  */
  78 extern int atoi __P ((__const char *__nptr));
  79 /* Convert a string to a long integer.  */
  80 extern long int atol __P ((__const char *__nptr));
  81
  82 #if defined (__GNUC__) && defined (__USE_MISC)
  83 /* These functions will part of the standard C library in ISO C 9X.  */
  84 extern long long int atoll __P ((__const char *__nptr));
  85 #endif
  86
  87 /* Convert a string to a floating-point number.  */
  88 extern double strtod __P ((__const char *__nptr, char **__endptr));
  89
  90 #ifdef  __USE_GNU
  91 /* Likewise for `float' and `long double' sizes of floating-point numbers.  */
  92 extern float strtof __P ((__const char *__nptr, char **__endptr));
  93 extern __long_double_t strtold __P ((__const char *__nptr, char **__endptr));
  94 #endif
  95
  96 /* Convert a string to a long integer.  */
  97 extern long int strtol __P ((__const char *__nptr, char **__endptr,
  98                              int __base));
  99 /* Convert a string to an unsigned long integer.  */
 100 extern unsigned long int strtoul __P ((__const char *__nptr,
 101                                        char **__endptr, int __base));
 102
 103 #if defined (__GNUC__) && defined (__USE_BSD)
 104 /* Convert a string to a quadword integer.  */
 105 extern long long int strtoq __P ((__const char *__nptr, char **__endptr,
 106                                   int __base));
 107 /* Convert a string to an unsigned quadword integer.  */
 108 extern unsigned long long int strtouq __P ((__const char *__nptr,
 109                                             char **__endptr, int __base));
 110 #endif /* GCC and use BSD.  */
 111
 112 #if defined (__GNUC__) && defined (__USE_MISC)
 113 /* These functions will part of the standard C library in ISO C 9X.  */
 114
 115 /* Convert a string to a quadword integer.  */
 116 extern long long int strtoll __P ((__const char *__nptr, char **__endptr,
 117                                    int __base));
 118 /* Convert a string to an unsigned quadword integer.  */
 119 extern unsigned long long int strtoull __P ((__const char *__nptr,
 120                                              char **__endptr, int __base));
 121 #endif /* GCC and use MISC.  */
 122
 123
 124
 125 /* The internal entry points for `strtoX' take an extra flag argument
 126    saying whether or not to parse locale-dependent number grouping.  */
 127
 128 extern double __strtod_internal __P ((__const char *__nptr,
 129                                       char **__endptr, int __group));
 130 extern float __strtof_internal __P ((__const char *__nptr, char **__endptr,
 131                                      int __group));
 132 extern __long_double_t __strtold_internal __P ((__const char *__nptr,
 133                                                 char **__endptr, int __group));
 134 extern long int __strtol_internal __P ((__const char *__nptr, char **__endptr,
 135                                         int __base, int __group));
 136 extern unsigned long int __strtoul_internal __P ((__const char *__nptr,
 137                                                   char **__endptr, int __base,
 138                                                   int __group));
 139 #ifdef __GNUC__
 140 extern long long int __strtoq_internal __P ((__const char *__nptr,
 141                                              char **__endptr, int __base,
 142                                              int __group));
 143 extern unsigned long long int __strtouq_internal __P ((__const char *__nptr,
 144                                                        char **__endptr,
 145                                                        int __base,
 146                                                        int __group));
 147 #endif /* GCC */
 148
 149 #if defined (__OPTIMIZE__) && __GNUC__ >= 2
 150 /* Define inline functions which call the internal entry points.  */
 151
 152 extern __inline double strtod (__const char *__nptr, char **__endptr)
 153 { return __strtod_internal (__nptr, __endptr, 0); }
 154 extern __inline long int strtol (__const char *__nptr,
 155                                  char **__endptr, int __base)
 156 { return __strtol_internal (__nptr, __endptr, __base, 0); }
 157 extern __inline unsigned long int strtoul (__const char *__nptr,
 158                                            char **__endptr, int __base)
 159 { return __strtoul_internal (__nptr, __endptr, __base, 0); }
 160
 161 #ifdef __USE_GNU
 162 extern __inline float strtof (__const char *__nptr, char **__endptr)
 163 { return __strtof_internal (__nptr, __endptr, 0); }
 164 extern __inline __long_double_t strtold (__const char *__nptr, char **__endptr)
 165 { return __strtold_internal (__nptr, __endptr, 0); }
 166 #endif
 167
 168 #ifdef __USE_BSD
 169 extern __inline long long int strtoq (__const char *__nptr, char **__endptr,
 170                                       int __base)
 171 { return __strtoq_internal (__nptr, __endptr, __base, 0); }
 172 extern __inline unsigned long long int strtouq (__const char *__nptr,
 173                                                 char **__endptr, int __base)
 174 { return __strtouq_internal (__nptr, __endptr, __base, 0); }
 175 #endif
 176
 177 #ifdef __USE_MISC
 178 extern __inline long long int strtoll (__const char *__nptr, char **__endptr,
 179                                        int __base)
 180 { return __strtoq_internal (__nptr, __endptr, __base, 0); }
 181 extern __inline unsigned long long int strtoull (__const char *__nptr,
 182                                                  char **__endptr, int __base)
 183 { return __strtouq_internal (__nptr, __endptr, __base, 0); }
 184 #endif
 185
 186 extern __inline double atof (__const char *__nptr)
 187 { return strtod (__nptr, (char **) NULL); }
 188 extern __inline int atoi (__const char *__nptr)
 189 { return (int) strtol (__nptr, (char **) NULL, 10); }
 190 extern __inline long int atol (__const char *__nptr)
 191 { return strtol (__nptr, (char **) NULL, 10); }
 192
 193 #ifdef __USE_MISC
 194 extern __inline long long int atoll (__const char *__nptr)
 195 { return strtoll (__nptr, (char **) NULL, 10); }
 196 #endif
 197 #endif /* Optimizing GCC >=2.  */
 198
 199
 200 #if defined(__USE_SVID) || defined(__USE_XOPEN_EXTENDED)
 201 /* Convert N to base 64 using the digits "./0-9A-Za-z", least-significant
 202    digit first.  Returns a pointer to static storage overwritten by the
 203    next call.  */
 204 extern char *l64a __P ((long int __n));
 205
 206 /* Read a number from a string S in base 64 as above.  */
 207 extern long int a64l __P ((__const char *__s));
 208
 209
 210 #include <sys/types.h>  /* we need int32_t... */
 211
 212 /* These are the functions that actually do things.  The `random', `srandom',
 213    `initstate' and `setstate' functions are those from BSD Unices.
 214    The `rand' and `srand' functions are required by the ANSI standard.
 215    We provide both interfaces to the same random number generator.  */
 216 /* Return a random long integer between 0 and RAND_MAX inclusive.  */
 217 extern int32_t __random __P ((void));
 218 extern int32_t random __P ((void));
 219
 220 /* Seed the random number generator with the given number.  */
 221 extern void __srandom __P ((unsigned int __seed));
 222 extern void srandom __P ((unsigned int __seed));
 223
 224 /* Initialize the random number generator to use state buffer STATEBUF,
 225    of length STATELEN, and seed it with SEED.  Optimal lengths are 8, 16,
 226    32, 64, 128 and 256, the bigger the better; values less than 8 will
 227    cause an error and values greater than 256 will be rounded down.  */
 228 extern __ptr_t __initstate __P ((unsigned int __seed, __ptr_t __statebuf,
 229                                  size_t __statelen));
 230 extern __ptr_t initstate __P ((unsigned int __seed, __ptr_t __statebuf,
 231                                size_t __statelen));
 232
 233 /* Switch the random number generator to state buffer STATEBUF,
 234    which should have been previously initialized by `initstate'.  */
 235 extern __ptr_t __setstate __P ((__ptr_t __statebuf));
 236 extern __ptr_t setstate __P ((__ptr_t __statebuf));
 237
 238
 239 #ifdef __USE_MISC
 240 /* Reentrant versions of the `random' family of functions.
 241    These functions all use the following data structure to contain
 242    state, rather than global state variables.  */
 243
 244 struct random_data
 245   {
 246     int32_t *fptr;              /* Front pointer.  */
 247     int32_t *rptr;              /* Rear pointer.  */
 248     int32_t *state;             /* Array of state values.  */
 249     int rand_type;              /* Type of random number generator.  */
 250     int rand_deg;               /* Degree of random number generator.  */
 251     int rand_sep;               /* Distance between front and rear.  */
 252     int32_t *end_ptr;           /* Pointer behind state table.  */
 253   };
 254
 255 extern int __random_r __P ((struct random_data *__buf, int32_t *__result));
 256 extern int random_r __P ((struct random_data *__buf, int32_t *__result));
 257
 258 extern int __srandom_r __P ((unsigned int __seed, struct random_data *__buf));
 259 extern int srandom_r __P ((unsigned int __seed, struct random_data *__buf));
 260
 261 extern int __initstate_r __P ((unsigned int __seed, __ptr_t __statebuf,
 262                                size_t __statelen, struct random_data *__buf));
 263 extern int initstate_r __P ((unsigned int __seed, __ptr_t __statebuf,
 264                              size_t __statelen, struct random_data *__buf));
 265
 266 extern int __setstate_r __P ((__ptr_t __statebuf, struct random_data *__buf));
 267 extern int setstate_r __P ((__ptr_t __statebuf, struct random_data *__buf));
 268 #endif  /* Use misc.  */
 269 #endif  /* Use SVID || extended X/Open.  */
 270
 271
 272 /* Return a random integer between 0 and RAND_MAX inclusive.  */
 273 extern int rand __P ((void));
 274 /* Seed the random number generator with the given number.  */
 275 extern void srand __P ((unsigned int __seed));
 276
 277 #ifdef __USE_MISC
 278 /* Reentrant interface according to POSIX.1.  */
 279 extern int __rand_r __P ((unsigned int *__seed));
 280 extern int rand_r __P ((unsigned int *__seed));
 281 #endif
 282
 283
 284 #if defined(__USE_SVID) || defined(__USE_XOPEN)
 285 /* System V style 48-bit random number generator functions.  */
 286
 287 /* Return non-negative, double-precision floating-point value in [0.0,1.0).  */
 288 extern double drand48 __P ((void));
 289 extern double erand48 __P ((unsigned short int __xsubi[3]));
 290
 291 /* Return non-negative, long integer in [0,2^31).  */
 292 extern long lrand48 __P ((void));
 293 extern long nrand48 __P ((unsigned short int __xsubi[3]));
 294
 295 /* Return signed, long integers in [-2^31,2^31).  */
 296 extern long mrand48 __P ((void));
 297 extern long jrand48 __P ((unsigned short int __xsubi[3]));
 298
 299 /* Seed random number generator.  */
 300 extern void srand48 __P ((long __seedval));
 301 extern unsigned short int *seed48 __P ((unsigned short int __seed16v[3]));
 302 extern void lcong48 __P ((unsigned short int __param[7]));
 303
 304 /* Data structure for communication with thread safe versions.  */
 305 struct drand48_data
 306   {
 307     unsigned short int x[3];    /* Current state.  */
 308     unsigned short int a[3];    /* Factor in congruential formula.  */
 309     unsigned short int c;       /* Additive const. in congruential formula.  */
 310     unsigned short int old_x[3]; /* Old state.  */
 311     int init;                   /* Flag for initializing.  */
 312   };
 313
 314 #ifdef __USE_MISC
 315 /* Return non-negative, double-precision floating-point value in [0.0,1.0).  */
 316 extern int drand48_r __P ((struct drand48_data *__buffer, double *__result));
 317 extern int erand48_r __P ((unsigned short int __xsubi[3],
 318                            struct drand48_data *__buffer, double *__result));
 319
 320 /* Return non-negative, long integer in [0,2^31).  */
 321 extern int lrand48_r __P ((struct drand48_data *__buffer, long *__result));
 322 extern int nrand48_r __P ((unsigned short int __xsubi[3],
 323                            struct drand48_data *__buffer, long *__result));
 324
 325 /* Return signed, long integers in [-2^31,2^31).  */
 326 extern int mrand48_r __P ((struct drand48_data *__buffer, long *__result));
 327 extern int jrand48_r __P ((unsigned short int __xsubi[3],
 328                            struct drand48_data *__buffer, long *__result));
 329
 330 /* Seed random number generator.  */
 331 extern int srand48_r __P ((long __seedval, struct drand48_data *__buffer));
 332 extern int seed48_r __P ((unsigned short int __seed16v[3],
 333                           struct drand48_data *__buffer));
 334 extern int lcong48_r __P ((unsigned short int __param[7],
 335                            struct drand48_data *__buffer));
 336 #endif  /* Use misc.  */
 337
 338 /* Internal function to compute next state of the generator.  */
 339 extern int __drand48_iterate __P ((unsigned short int __xsubi[3],
 340                                    struct drand48_data *__buffer));
 341 #endif  /* Use SVID or X/Open.  */
 342
 343
 344 /* Allocate SIZE bytes of memory.  */
 345 extern __ptr_t malloc __P ((size_t __size));
 346 /* Re-allocate the previously allocated block
 347    in __ptr_t, making the new block SIZE bytes long.  */
 348 extern __ptr_t realloc __P ((__ptr_t __ptr, size_t __size));
 349 /* Allocate NMEMB elements of SIZE bytes each, all initialized to 0.  */
 350 extern __ptr_t calloc __P ((size_t __nmemb, size_t __size));
 351 /* Free a block allocated by `malloc', `realloc' or `calloc'.  */
 352 extern void free __P ((__ptr_t __ptr));
 353
 354 #ifdef  __USE_MISC
 355 /* Free a block.  An alias for `free'.  (Sun Unices).  */
 356 extern void cfree __P ((__ptr_t __ptr));
 357 #endif /* Use misc.  */
 358
 359 #if defined(__USE_GNU) || defined(__USE_BSD) || defined(__USE_MISC)
 360 #include <alloca.h>
 361 #endif /* Use GNU, BSD, or misc.  */
 362
 363 #if defined(__USE_BSD) || defined(__USE_XOPEN_EXTENDED)
 364 /* Allocate SIZE bytes on a page boundary.  The storage cannot be freed.  */
 365 extern __ptr_t valloc __P ((size_t __size));
 366 #endif
 367
 368
 369 /* Abort execution and generate a core-dump.  */
 370 extern void abort __P ((void)) __attribute__ ((__noreturn__));
 371
 372
 373 /* Register a function to be called when `exit' is called.  */
 374 extern int atexit __P ((void (*__func) (void)));
 375
 376 #ifdef  __USE_MISC
 377 /* Register a function to be called with the status
 378    given to `exit' and the given argument.  */
 379 extern int __on_exit __P ((void (*__func) (int __status, __ptr_t __arg),
 380                            __ptr_t __arg));
 381 extern int on_exit __P ((void (*__func) (int __status, __ptr_t __arg),
 382                          __ptr_t __arg));
 383 #endif
 384
 385 /* Call all functions registered with `atexit' and `on_exit',
 386    in the reverse of the order in which they were registered
 387    perform stdio cleanup, and terminate program execution with STATUS.  */
 388 extern void exit __P ((int __status)) __attribute__ ((__noreturn__));
 389
 390
 391 /* Return the value of envariable NAME, or NULL if it doesn't exist.  */
 392 extern char *getenv __P ((__const char *__name));
 393
 394 /* This function is similar to the above but returns NULL if the
 395    programs is running with SUID or SGID enabled.  */
 396 extern char *__secure_getenv __P ((__const char *__name));
 397
 398 #if defined(__USE_SVID) || defined(__USE_XOPEN)
 399 /* The SVID says this is in <stdio.h>, but this seems a better place.   */
 400 /* Put STRING, which is of the form "NAME=VALUE", in the environment.
 401    If there is no `=', remove NAME from the environment.  */
 402 extern int putenv __P ((__const char *__string));
 403 #endif
 404
 405 #ifdef  __USE_BSD
 406 /* Set NAME to VALUE in the environment.
 407    If REPLACE is nonzero, overwrite an existing value.  */
 408 extern int setenv __P ((__const char *__name, __const char *__value,
 409                         int __replace));
 410
 411 /* Remove the variable NAME from the environment.  */
 412 extern void unsetenv __P ((__const char *__name));
 413 #endif
 414
 415 #ifdef  __USE_MISC
 416 /* The `clearenv' was planned to be added to POSIX.1 but probably
 417    never made it.  Nevertheless the POSIX.9 standard (POSIX bindings
 418    for Fortran 77) requires this function.  */
 419 extern int __clearenv __P ((void));
 420 extern int clearenv __P ((void));
 421 #endif
 422
 423
 424 #if defined(__USE_MISC) || defined(__USE_XOPEN_EXTENDED)
 425 /* Generate a unique temporary file name from TEMPLATE.
 426    The last six characters of TEMPLATE must be "XXXXXX";
 427    they are replaced with a string that makes the file name unique.
 428    Returns TEMPLATE, or a null pointer if it cannot get a unique file name.  */
 429 extern char *mktemp __P ((char *__template));
 430
 431 /* Generate a unique temporary file name from TEMPLATE.
 432    The last six characters of TEMPLATE must be "XXXXXX";
 433    they are replaced with a string that makes the filename unique.
 434    Returns a file descriptor open on the file for reading and writing,
 435    or -1 if it cannot create a uniquely-named file.  */
 436 extern int mkstemp __P ((char *__template));
 437 #endif
 438
 439
 440 /* Execute the given line as a shell command.  */
 441 extern int system __P ((__const char *__command));
 442
 443
 444 #ifdef  __USE_GNU
 445 /* Return a malloc'd string containing the canonical absolute name of the
 446    named file.  The last file name component need not exist, and may be a
 447    symlink to a nonexistent file.  */
 448 extern char *canonicalize_file_name __P ((__const char *__name));
 449 #endif
 450
 451 #if defined(__USE_BSD) || defined(__USE_XOPEN_EXTENDED)
 452 /* Return the canonical absolute name of file NAME.  The last file name
 453    component need not exist, and may be a symlink to a nonexistent file.
 454    If RESOLVED is null, the result is malloc'd; otherwise, if the canonical
 455    name is PATH_MAX chars or more, returns null with `errno' set to
 456    ENAMETOOLONG; if the name fits in fewer than PATH_MAX chars, returns the
 457    name in RESOLVED.  */
 458 extern char *realpath __P ((__const char *__name, char *__resolved));
 459 #endif
 460
 461
 462 /* Shorthand for type of comparison functions.  */
 463 #ifndef __COMPAR_FN_T
 464 #define __COMPAR_FN_T
 465 typedef int (*__compar_fn_t) __P ((__const __ptr_t, __const __ptr_t));
 466 #endif
 467
 468 #ifdef  __USE_GNU
 469 typedef __compar_fn_t comparison_fn_t;
 470 #endif
 471
 472 /* Do a binary search for KEY in BASE, which consists of NMEMB elements
 473    of SIZE bytes each, using COMPAR to perform the comparisons.  */
 474 extern __ptr_t bsearch __P ((__const __ptr_t __key, __const __ptr_t __base,
 475                              size_t __nmemb, size_t __size,
 476                              __compar_fn_t __compar));
 477
 478 /* Sort NMEMB elements of BASE, of SIZE bytes each,
 479    using COMPAR to perform the comparisons.  */
 480 extern void qsort __P ((__ptr_t __base, size_t __nmemb, size_t __size,
 481                         __compar_fn_t __compar));
 482
 483
 484 /* Return the absolute value of X.  */
 485 extern int abs __P ((int __x)) __attribute__ ((__const__));
 486 extern long int labs __P ((long int __x)) __attribute__ ((__const__));
 487 #ifdef __USE_GNU
 488 extern long long int llabs __P ((long long int __x)) __attribute__ ((__const__));
 489 #endif
 490
 491
 492 /* Return the `div_t', `ldiv_t' or `lldiv_t' representation
 493    of the value of NUMER over DENOM. */
 494 /* GCC may have built-ins for these someday.  */
 495 extern div_t div __P ((int __numer, int __denom)) __attribute__ ((__const__));
 496 extern ldiv_t ldiv __P ((long int __numer, long int __denom)) __attribute__ ((__const__));
 497 #ifdef __USE_GNU
 498 extern lldiv_t lldiv __P ((long long int __numer, long long int __denom)) __attribute__ ((__const__));
 499 #endif
 500
 501
 502 #if defined(__USE_SVID) || defined(__USE_XOPEN_EXTENDED)
 503 /* Convert floating point numbers to strings.  The returned values are
 504    valid only until another call to the same function.  */
 505
 506 /* Convert VALUE to a string with NDIGIT digits and return a pointer to
 507    this.  Set *DECPT with the position of the decimal character and *SIGN
 508    with the sign of the number.  */
 509 extern char *ecvt __P ((double __value, int __ndigit, int *__decpt,
 510                         int *__sign));
 511
 512 /* Convert VALUE to a string rounded to NDIGIT decimal digits.  Set *DECPT
 513    with the position of the decimal character and *SIGN with the sign of
 514    the number.  */
 515 extern char *fcvt __P ((double __value, int __ndigit, int *__decpt,
 516                         int *__sign));
 517
 518 /* If possible convert VALUE to a string with NDIGIT significant digits.
 519    Otherwise use exponential representation.  The resulting string will
 520    be written to BUF.  */
 521 extern char *gcvt __P ((double __value, int __ndigit, char *__buf));
 522
 523 /* Long double versions of above functions.  */
 524 extern char *qecvt __P ((__long_double_t __value, int __ndigit, int *__decpt,
 525                          int *__sign));
 526 extern char *qfcvt __P ((__long_double_t __value, int __ndigit, int *__decpt,
 527                          int *__sign));
 528 extern char *qgcvt __P ((__long_double_t __value, int __ndigit, char *__buf));
 529
 530
 531 #ifdef __USE_MISC
 532 /* Reentrant version of the functions above which provide their own
 533    buffers.  */
 534 extern int ecvt_r __P ((double __value, int __ndigit, int *__decpt,
 535                         int *__sign, char *__buf, size_t __len));
 536 extern int fcvt_r __P ((double __value, int __ndigit, int *__decpt,
 537                         int *__sign, char *__buf, size_t __len));
 538
 539 extern int qecvt_r __P ((__long_double_t __value, int __ndigit, int *__decpt,
 540                          int *__sign, char *__buf, size_t __len));
 541 extern int qfcvt_r __P ((__long_double_t __value, int __ndigit, int *__decpt,
 542                          int *__sign, char *__buf, size_t __len));
 543 #endif  /* misc */
 544 #endif  /* use MISC || use X/Open Unix */
 545
 546
 547 /* Return the length of the multibyte character
 548    in S, which is no longer than N.  */
 549 extern int mblen __P ((__const char *__s, size_t __n));
 550 /* Return the length of the given multibyte character,
 551    putting its `wchar_t' representation in *PWC.  */
 552 extern int mbtowc __P ((wchar_t *__pwc, __const char *__s, size_t __n));
 553 /* Put the multibyte character represented
 554    by WCHAR in S, returning its length.  */
 555 extern int wctomb __P ((char *__s, wchar_t __wchar));
 556
 557
 558 /* Convert a multibyte string to a wide char string.  */
 559 extern size_t mbstowcs __P ((wchar_t *__pwcs, __const char *__s, size_t __n));
 560 /* Convert a wide char string to multibyte string.  */
 561 extern size_t wcstombs __P ((char *__s, __const wchar_t *__pwcs, size_t __n));
 562
 563
 564 #ifdef __USE_SVID
 565 /* Determine whether the string value of RESPONSE matches the affirmation
 566    or negative response expression as specified by the LC_MESSAGES category
 567    in the program's current locale.  Returns 1 if affirmative, 0 if
 568    negative, and -1 if not matching.  */
 569 extern int rpmatch __P ((__const char *__response));
 570 #endif
 571
 572
 573 #ifdef __USE_XOPEN_EXTENDED
 574 /* Parse comma separated suboption from *OPTIONP and match against
 575    strings in TOKENS.  If found return index and set *VALUEP to
 576    optional value introduced by an equal sign.  If the suboption is
 577    not part of TOKENS return in *VALUEP beginning of unknown
 578    suboption.  On exit *OPTIONP is set to the beginning of the next
 579    otken or at the terminating NUL character.  */
 580 extern int getsubopt __P ((char **__optionp, __const char *__const *__tokens,
 581                            char **__valuep));
 582 #endif
 583
 584
 585 #ifdef __USE_XOPEN
 586
 587 /* Setup DES tables according KEY.  */
 588 extern void setkey __P ((__const char *__key));
 589 #endif
 590
 591
 592 __END_DECLS
 593
 594 #endif /* stdlib.h  */