time/time.h

   1 /* Copyright (C) 1991-1999,2000,2001,2002,2003,2006
   2         Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 /*
  21  *      ISO C99 Standard: 7.23 Date and time    <time.h>
  22  */
  23
  24 #ifndef _TIME_H
  25
  26 #if (! defined __need_time_t && !defined __need_clock_t && \
  27      ! defined __need_timespec)
  28 # define _TIME_H        1
  29 # include <features.h>
  30
  31 __BEGIN_DECLS
  32
  33 #endif
  34
  35 #ifdef  _TIME_H
  36 /* Get size_t and NULL from <stddef.h>.  */
  37 # define __need_size_t
  38 # define __need_NULL
  39 # include <stddef.h>
  40
  41 /* This defines CLOCKS_PER_SEC, which is the number of processor clock
  42    ticks per second.  */
  43 # include <bits/time.h>
  44
  45 /* This is the obsolete POSIX.1-1988 name for the same constant.  */
  46 # if !defined __STRICT_ANSI__ && !defined __USE_XOPEN2K
  47 #  ifndef CLK_TCK
  48 #   define CLK_TCK      CLOCKS_PER_SEC
  49 #  endif
  50 # endif
  51
  52 #endif /* <time.h> included.  */
  53
  54 #if !defined __clock_t_defined && (defined _TIME_H || defined __need_clock_t)
  55 # define __clock_t_defined      1
  56
  57 # include <bits/types.h>
  58
  59 __BEGIN_NAMESPACE_STD
  60 /* Returned by `clock'.  */
  61 typedef __clock_t clock_t;
  62 __END_NAMESPACE_STD
  63 #if defined __USE_XOPEN || defined __USE_POSIX || defined __USE_MISC
  64 __USING_NAMESPACE_STD(clock_t)
  65 #endif
  66
  67 #endif /* clock_t not defined and <time.h> or need clock_t.  */
  68 #undef  __need_clock_t
  69
  70 #if !defined __time_t_defined && (defined _TIME_H || defined __need_time_t)
  71 # define __time_t_defined       1
  72
  73 # include <bits/types.h>
  74
  75 __BEGIN_NAMESPACE_STD
  76 /* Returned by `time'.  */
  77 typedef __time_t time_t;
  78 __END_NAMESPACE_STD
  79 #if defined __USE_POSIX || defined __USE_MISC || defined __USE_SVID
  80 __USING_NAMESPACE_STD(time_t)
  81 #endif
  82
  83 #endif /* time_t not defined and <time.h> or need time_t.  */
  84 #undef  __need_time_t
  85
  86 #if !defined __clockid_t_defined && \
  87    ((defined _TIME_H && defined __USE_POSIX199309) || defined __need_clockid_t)
  88 # define __clockid_t_defined    1
  89
  90 # include <bits/types.h>
  91
  92 /* Clock ID used in clock and timer functions.  */
  93 typedef __clockid_t clockid_t;
  94
  95 #endif /* clockid_t not defined and <time.h> or need clockid_t.  */
  96 #undef  __clockid_time_t
  97
  98 #if !defined __timer_t_defined && \
  99     ((defined _TIME_H && defined __USE_POSIX199309) || defined __need_timer_t)
 100 # define __timer_t_defined      1
 101
 102 # include <bits/types.h>
 103
 104 /* Timer ID returned by `timer_create'.  */
 105 typedef __timer_t timer_t;
 106
 107 #endif /* timer_t not defined and <time.h> or need timer_t.  */
 108 #undef  __need_timer_t
 109
 110
 111 #if !defined __timespec_defined &&                              \
 112     ((defined _TIME_H &&                                        \
 113       (defined __USE_POSIX199309 || defined __USE_MISC)) ||     \
 114       defined __need_timespec)
 115 # define __timespec_defined     1
 116
 117 # include <bits/types.h>        /* This defines __time_t for us.  */
 118
 119 /* POSIX.1b structure for a time value.  This is like a `struct timeval' but
 120    has nanoseconds instead of microseconds.  */
 121 struct timespec
 122   {
 123     __time_t tv_sec;            /* Seconds.  */
 124     long int tv_nsec;           /* Nanoseconds.  */
 125   };
 126
 127 #endif /* timespec not defined and <time.h> or need timespec.  */
 128 #undef  __need_timespec
 129
 130
 131 #ifdef  _TIME_H
 132 __BEGIN_NAMESPACE_STD
 133 /* Used by other time functions.  */
 134 struct tm
 135 {
 136   int tm_sec;                   /* Seconds.     [0-60] (1 leap second) */
 137   int tm_min;                   /* Minutes.     [0-59] */
 138   int tm_hour;                  /* Hours.       [0-23] */
 139   int tm_mday;                  /* Day.         [1-31] */
 140   int tm_mon;                   /* Month.       [0-11] */
 141   int tm_year;                  /* Year - 1900.  */
 142   int tm_wday;                  /* Day of week. [0-6] */
 143   int tm_yday;                  /* Days in year.[0-365] */
 144   int tm_isdst;                 /* DST.         [-1/0/1]*/
 145
 146 #ifdef  __USE_BSD
 147   long int tm_gmtoff;           /* Seconds east of UTC.  */
 148   __const char *tm_zone;        /* Timezone abbreviation.  */
 149 #else
 150   long int __tm_gmtoff;         /* Seconds east of UTC.  */
 151   __const char *__tm_zone;      /* Timezone abbreviation.  */
 152 #endif
 153 };
 154 __END_NAMESPACE_STD
 155 #if defined __USE_XOPEN || defined __USE_POSIX || defined __USE_MISC
 156 __USING_NAMESPACE_STD(tm)
 157 #endif
 158
 159
 160 #ifdef __USE_POSIX199309
 161 /* POSIX.1b structure for timer start values and intervals.  */
 162 struct itimerspec
 163   {
 164     struct timespec it_interval;
 165     struct timespec it_value;
 166   };
 167
 168 /* We can use a simple forward declaration.  */
 169 struct sigevent;
 170
 171 #endif  /* POSIX.1b */
 172
 173 #ifdef __USE_XOPEN2K
 174 # ifndef __pid_t_defined
 175 typedef __pid_t pid_t;
 176 #  define __pid_t_defined
 177 # endif
 178 #endif
 179
 180
 181 __BEGIN_NAMESPACE_STD
 182 /* Time used by the program so far (user time + system time).
 183    The result / CLOCKS_PER_SECOND is program time in seconds.  */
 184 extern clock_t clock (void) __THROW;
 185
 186 /* Return the current time and put it in *TIMER if TIMER is not NULL.  */
 187 extern time_t time (time_t *__timer) __THROW;
 188
 189 /* Return the difference between TIME1 and TIME0.  */
 190 extern double difftime (time_t __time1, time_t __time0)
 191      __THROW __attribute__ ((__const__));
 192
 193 /* Return the `time_t' representation of TP and normalize TP.  */
 194 extern time_t mktime (struct tm *__tp) __THROW;
 195
 196
 197 /* Format TP into S according to FORMAT.
 198    Write no more than MAXSIZE characters and return the number
 199    of characters written, or 0 if it would exceed MAXSIZE.  */
 200 extern size_t strftime (char *__restrict __s, size_t __maxsize,
 201                         __const char *__restrict __format,
 202                         __const struct tm *__restrict __tp) __THROW;
 203 __END_NAMESPACE_STD
 204
 205 # ifdef __USE_XOPEN
 206 /* Parse S according to FORMAT and store binary time information in TP.
 207    The return value is a pointer to the first unparsed character in S.  */
 208 extern char *strptime (__const char *__restrict __s,
 209                        __const char *__restrict __fmt, struct tm *__tp)
 210      __THROW;
 211 # endif
 212
 213 # ifdef __USE_GNU
 214 /* Similar to the two functions above but take the information from
 215    the provided locale and not the global locale.  */
 216 # include <xlocale.h>
 217
 218 extern size_t strftime_l (char *__restrict __s, size_t __maxsize,
 219                           __const char *__restrict __format,
 220                           __const struct tm *__restrict __tp,
 221                           __locale_t __loc) __THROW;
 222
 223 extern char *strptime_l (__const char *__restrict __s,
 224                          __const char *__restrict __fmt, struct tm *__tp,
 225                          __locale_t __loc) __THROW;
 226 # endif
 227
 228
 229 __BEGIN_NAMESPACE_STD
 230 /* Return the `struct tm' representation of *TIMER
 231    in Universal Coordinated Time (aka Greenwich Mean Time).  */
 232 extern struct tm *gmtime (__const time_t *__timer) __THROW;
 233
 234 /* Return the `struct tm' representation
 235    of *TIMER in the local timezone.  */
 236 extern struct tm *localtime (__const time_t *__timer) __THROW;
 237 __END_NAMESPACE_STD
 238
 239 # if defined __USE_POSIX || defined __USE_MISC
 240 /* Return the `struct tm' representation of *TIMER in UTC,
 241    using *TP to store the result.  */
 242 extern struct tm *gmtime_r (__const time_t *__restrict __timer,
 243                             struct tm *__restrict __tp) __THROW;
 244
 245 /* Return the `struct tm' representation of *TIMER in local time,
 246    using *TP to store the result.  */
 247 extern struct tm *localtime_r (__const time_t *__restrict __timer,
 248                                struct tm *__restrict __tp) __THROW;
 249 # endif /* POSIX or misc */
 250
 251 __BEGIN_NAMESPACE_STD
 252 /* Return a string of the form "Day Mon dd hh:mm:ss yyyy\n"
 253    that is the representation of TP in this format.  */
 254 extern char *asctime (__const struct tm *__tp) __THROW;
 255
 256 /* Equivalent to `asctime (localtime (timer))'.  */
 257 extern char *ctime (__const time_t *__timer) __THROW;
 258 __END_NAMESPACE_STD
 259
 260 # if defined __USE_POSIX || defined __USE_MISC
 261 /* Reentrant versions of the above functions.  */
 262
 263 /* Return in BUF a string of the form "Day Mon dd hh:mm:ss yyyy\n"
 264    that is the representation of TP in this format.  */
 265 extern char *asctime_r (__const struct tm *__restrict __tp,
 266                         char *__restrict __buf) __THROW;
 267
 268 /* Equivalent to `asctime_r (localtime_r (timer, *TMP*), buf)'.  */
 269 extern char *ctime_r (__const time_t *__restrict __timer,
 270                       char *__restrict __buf) __THROW;
 271 # endif /* POSIX or misc */
 272
 273
 274 /* Defined in localtime.c.  */
 275 extern char *__tzname[2];       /* Current timezone names.  */
 276 extern int __daylight;          /* If daylight-saving time is ever in use.  */
 277 extern long int __timezone;     /* Seconds west of UTC.  */
 278
 279
 280 # ifdef __USE_POSIX
 281 /* Same as above.  */
 282 extern char *tzname[2];
 283
 284 /* Set time conversion information from the TZ environment variable.
 285    If TZ is not defined, a locale-dependent default is used.  */
 286 extern void tzset (void) __THROW;
 287 # endif
 288
 289 # if defined __USE_SVID || defined __USE_XOPEN
 290 extern int daylight;
 291 extern long int timezone;
 292 # endif
 293
 294 # ifdef __USE_SVID
 295 /* Set the system time to *WHEN.
 296    This call is restricted to the superuser.  */
 297 extern int stime (__const time_t *__when) __THROW;
 298 # endif
 299
 300
 301 /* Nonzero if YEAR is a leap year (every 4 years,
 302    except every 100th isn't, and every 400th is).  */
 303 # define __isleap(year) \
 304   ((year) % 4 == 0 && ((year) % 100 != 0 || (year) % 400 == 0))
 305
 306
 307 # ifdef __USE_MISC
 308 /* Miscellaneous functions many Unices inherited from the public domain
 309    localtime package.  These are included only for compatibility.  */
 310
 311 /* Like `mktime', but for TP represents Universal Time, not local time.  */
 312 extern time_t timegm (struct tm *__tp) __THROW;
 313
 314 /* Another name for `mktime'.  */
 315 extern time_t timelocal (struct tm *__tp) __THROW;
 316
 317 /* Return the number of days in YEAR.  */
 318 extern int dysize (int __year) __THROW  __attribute__ ((__const__));
 319 # endif
 320
 321
 322 # ifdef __USE_POSIX199309
 323 /* Pause execution for a number of nanoseconds.
 324
 325    This function is a cancellation point and therefore not marked with
 326    __THROW.  */
 327 extern int nanosleep (__const struct timespec *__requested_time,
 328                       struct timespec *__remaining);
 329
 330
 331 /* Get resolution of clock CLOCK_ID.  */
 332 extern int clock_getres (clockid_t __clock_id, struct timespec *__res) __THROW;
 333
 334 /* Get current value of clock CLOCK_ID and store it in TP.  */
 335 extern int clock_gettime (clockid_t __clock_id, struct timespec *__tp) __THROW;
 336
 337 /* Set clock CLOCK_ID to value TP.  */
 338 extern int clock_settime (clockid_t __clock_id, __const struct timespec *__tp)
 339      __THROW;
 340
 341 #  ifdef __USE_XOPEN2K
 342 /* High-resolution sleep with the specified clock.
 343
 344    This function is a cancellation point and therefore not marked with
 345    __THROW.  */
 346 extern int clock_nanosleep (clockid_t __clock_id, int __flags,
 347                             __const struct timespec *__req,
 348                             struct timespec *__rem);
 349
 350 /* Return clock ID for CPU-time clock.  */
 351 extern int clock_getcpuclockid (pid_t __pid, clockid_t *__clock_id) __THROW;
 352 #  endif
 353
 354
 355 /* Create new per-process timer using CLOCK_ID.  */
 356 extern int timer_create (clockid_t __clock_id,
 357                          struct sigevent *__restrict __evp,
 358                          timer_t *__restrict __timerid) __THROW;
 359
 360 /* Delete timer TIMERID.  */
 361 extern int timer_delete (timer_t __timerid) __THROW;
 362
 363 /* Set timer TIMERID to VALUE, returning old value in OVLAUE.  */
 364 extern int timer_settime (timer_t __timerid, int __flags,
 365                           __const struct itimerspec *__restrict __value,
 366                           struct itimerspec *__restrict __ovalue) __THROW;
 367
 368 /* Get current value of timer TIMERID and store it in VLAUE.  */
 369 extern int timer_gettime (timer_t __timerid, struct itimerspec *__value)
 370      __THROW;
 371
 372 /* Get expiration overrun for timer TIMERID.  */
 373 extern int timer_getoverrun (timer_t __timerid) __THROW;
 374 # endif
 375
 376
 377 # ifdef __USE_XOPEN_EXTENDED
 378 /* Set to one of the following values to indicate an error.
 379      1  the DATEMSK environment variable is null or undefined,
 380      2  the template file cannot be opened for reading,
 381      3  failed to get file status information,
 382      4  the template file is not a regular file,
 383      5  an error is encountered while reading the template file,
 384      6  memory allication failed (not enough memory available),
 385      7  there is no line in the template that matches the input,
 386      8  invalid input specification Example: February 31 or a time is
 387         specified that can not be represented in a time_t (representing
 388         the time in seconds since 00:00:00 UTC, January 1, 1970) */
 389 extern int getdate_err;
 390
 391 /* Parse the given string as a date specification and return a value
 392    representing the value.  The templates from the file identified by
 393    the environment variable DATEMSK are used.  In case of an error
 394    `getdate_err' is set.
 395
 396    This function is a possible cancellation points and therefore not
 397    marked with __THROW.  */
 398 extern struct tm *getdate (__const char *__string);
 399 # endif
 400
 401 # ifdef __USE_GNU
 402 /* Since `getdate' is not reentrant because of the use of `getdate_err'
 403    and the static buffer to return the result in, we provide a thread-safe
 404    variant.  The functionality is the same.  The result is returned in
 405    the buffer pointed to by RESBUFP and in case of an error the return
 406    value is != 0 with the same values as given above for `getdate_err'.
 407
 408    This function is not part of POSIX and therefore no official
 409    cancellation point.  But due to similarity with an POSIX interface
 410    or due to the implementation it is a cancellation point and
 411    therefore not marked with __THROW.  */
 412 extern int getdate_r (__const char *__restrict __string,
 413                       struct tm *__restrict __resbufp);
 414 # endif
 415
 416 __END_DECLS
 417
 418 #endif /* <time.h> included.  */
 419
 420 #endif /* <time.h> not already included.  */