time/time.h

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