stdlib/stdlib.h

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