NAME
          irLBolt, irNap - Unix clock routines

     SYNOPSIS
          #include <irapi.h>

          int irLBolt ( );

          int irNap (int interval);


     DESCRIPTION
          Function irLBolt returns the lbolt time for the system.  The
          lbolt time is defined as the amount of time which has passed
          since the UNIX system was last booted.  However, after
          approximately 248 days this value will overflow to a large
          negative number.  The unit of time is hundredths of seconds.

          Function irNap sleeps for interval hundredths of seconds.
          This is a blocking sleep, therefore, unlike most other IRAPI
          functions, it will not return immediately.  Also, there will
          be no event indicating the completion of irNap.

     EVENTS
          No event results from the call to either of these functions.

     RETURN VALUE
          irLBolt, on success, returns the elapsed time since the last
          UNIX system reboot measured in hundredths of seconds.  A
          return value of -1 is a possibly valid return value, but is
          can also indicate that an error occurred in getting the sys-
          tem lbolt value.

          irNap returns IRR_FAIL on error, otherwise the number of
          ''unslept'' hundredths of seconds are returned; 0 indicating
          ''sleep'' to completion, a positive value indicating interr-
          uption due to a signal.

     ERROR
          irError is set as follows on error.

          IRER_SYSERROR on system call failure (see irSysError for
          additional information).

     CAVEAT
          Since irNap is a blocking function, it should not be used in
          typical IRAPI applications.

          These functions report values based on the inherent clock
          granularity of the currently supported hardware platform.
          This granularity is not guaranteed with future hardware
          platforms.

     WARNING
          Applications should never assume that lbolt will always be
          positive (0, -1, and any other negative value are possible
          lbolt values).  Applications should never assume that there
          is a maximum or minimum value for lbolt. Extra caution
          should be taken whenever using lbolt values due to the pos-
          sibility of it going negative after a long period of time.

          For example direct comparison of values returned by
          irLBolt(3IRAPI) will result in errors when irLBolt(3IRAPI)
          wraps around to a large negative value after approximately
          248 days.  The correct way to compare values returned by
          irLBolt(3IRAPI) is to subtract the values first, e.g.:

               time_start = irLBolt(3IRAPI);
               ... some time consuming work ...
               time_now = irLBolt(3IRPAI);

               if ( (time_now - time_start) > MAXTICKS ) {
                    statement1;
               } else {
                    statement2;
               }

          Done this way, even if irLBolt(3IRAPI) wraps around to a
          large negative value, even between when the time samples are
          taken, the subtraction will correctly determine the number
          of clock ticks between the start time and the current time.
          The only time this will fail is when the time difference
          exceeds approximately 248 days.

     SEE ALSO
          irTimer(3IRAPI), irTTTimer(3IRAPI), irRecogTimer(3IRAPI),
          IrPARAMETERS(4IRAPI).

     VERSION
          This is version 11/25/02 of this man page.