/usr/include/time.h 
Linux, SuSE 7.3, gcc -v 2.95.3
/* Returned by `clock'.  */
typedef __clock_t clock_t;

/* Returned by `time'.  */
typedef __time_t time_t;

/* Clock ID used in clock and timer functions. */
typedef __clockid_t clockid_t;

/* Timer ID returned by `timer_create'.  */
typedef __timer_t timer_t;

/* POSIX.1b structure for a time value.  This is
   like a `struct timeval' but has nanoseconds
   instead of microseconds.  */
struct timespec
  {
    long int tv_sec;     /* Seconds. */
    long int tv_nsec;    /* Nanoseconds. */
  };

/* Used by other time functions. */
struct tm
{
  int tm_sec;    /* Seconds. [0-60] (1 leap second) */
  int tm_min;    /* Minutes. [0-59]i                */
  int tm_hour;   /* Hours.   [0-23]i                */
  int tm_mday;   /* Day.     [1-31]                 */
  int tm_mon;    /* Month.   [0-11]                 */
  int tm_year;   /* Year     - 1900.                */
  int tm_wday;   /* Day of week. [0-6]              */
  int tm_yday;   /* Days in year. [0-365]           */
  int tm_isdst;  /* DST.     [-1/0/1]               */

# ifdef    __USE_BSD
  long int tm_gmtoff;      /* Seconds east of UTC.   */
  __const char *tm_zone;   /* Timezone abbreviation. */
# else 
  long int __tm_gmtoff;    /* Seconds east of UTC.   */
  __const char *__tm_zone; /* Timezone abbreviation. */
# endif 
};

#ifdef __USE_POSIX199309
/* POSIX.1b structure for timer start values and
   intervals. */
struct itimerspec
  {
    struct timespec it_interval;
    struct timespec it_value;
  };

/* We can use a simple forward declaration. */
struct sigevent;