bits/time.h

   1 /* System-dependent timing definitions.  Generic version.
   2    Copyright (C) 1996,1997,1999-2002,2003 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  * Never include this file directly; use <time.h> instead.
  22  */
  23
  24 #ifndef __need_timeval
  25 # ifndef _BITS_TIME_H
  26 #  define _BITS_TIME_H  1
  27
  28 /* ISO/IEC 9899:1990 7.12.1: <time.h>
  29    The macro `CLOCKS_PER_SEC' is the number per second of the value
  30    returned by the `clock' function. */
  31 /* CAE XSH, Issue 4, Version 2: <time.h>
  32    The value of CLOCKS_PER_SEC is required to be 1 million on all
  33    XSI-conformant systems. */
  34 #  define CLOCKS_PER_SEC  1000000l
  35
  36 #  if !defined __STRICT_ANSI__ && !defined __USE_XOPEN2K
  37 /* Even though CLOCKS_PER_SEC has such a strange value CLK_TCK
  38    presents the real value for clock ticks per second for the system.  */
  39 #   include <bits/types.h>
  40 extern long int __sysconf (int);
  41 #   define CLK_TCK ((__clock_t) __sysconf (2))  /* 2 is _SC_CLK_TCK */
  42 #  endif
  43
  44 #  ifdef __USE_POSIX199309
  45 /* Identifier for system-wide realtime clock.  */
  46 #   define CLOCK_REALTIME               0
  47 /* Monotonic system-wide clock.  */
  48 #   define CLOCK_MONOTONIC              1
  49 /* High-resolution timer from the CPU.  */
  50 #   define CLOCK_PROCESS_CPUTIME_ID     2
  51 /* Thread-specific CPU-time clock.  */
  52 #   define CLOCK_THREAD_CPUTIME_ID      3
  53
  54 /* Flag to indicate time is absolute.  */
  55 #   define TIMER_ABSTIME                1
  56 #  endif
  57
  58 # endif /* bits/time.h */
  59 #endif
  60
  61 #ifdef __need_timeval
  62 # undef __need_timeval
  63 # ifndef _STRUCT_TIMEVAL
  64 #  define _STRUCT_TIMEVAL       1
  65 #  include <bits/types.h>
  66
  67 /* A time value that is accurate to the nearest
  68    microsecond but also has a range of years.  */
  69 struct timeval
  70   {
  71     __time_t tv_sec;            /* Seconds.  */
  72     __suseconds_t tv_usec;      /* Microseconds.  */
  73   };
  74 # endif /* struct timeval */
  75 #endif  /* need timeval */