SECONDS(10.2)                                       SECONDS(10.2)

          seconds, ticks, HZ, MS2HZ, MS2TK, TK2MS, TK2SEC - kernel
          times and time conversions

          long    seconds(void)

          ulong   ticks(void)

          #define HZ          ...
          #define MS2HZ(t)    ...
          #define TK2SEC(t)   ...
          #define TK2MS(t)    ...
          #define MS2TK(m)    ...

          Seconds returns the system's idea of the current time as the
          number of seconds since the start of the epoch (00:00:00
          GMT, January 1, 1970).

          Ticks returns the number of system-dependent clock ticks
          since system boot.

          The system clock frequency is platform-dependent.  Several
          symbolic constants and macro functions are defined by the
          file mem.h to convert between different time units:

          HZ         The number of clock ticks per second.

          MS2HZ      Milliseconds per clock tick.

          TK2SEC(t)  Convert t clock ticks to seconds and return the
                     result (truncating not rounding).

          TK2MS(t)   Convert t clock ticks to milliseconds and return
                     the result.

          MS2TK(m)   Convert m milliseconds to clock ticks and return
                     the result (truncating).

          The functions are often used to calculate delays for timing
          functions, for instance:

               if(atactlrwait(dp->cp, DHmagic, 0, MS2TK(100))){