NAME

     timeradd, timersub, timerclear, timerisset, timercmp, timespecadd, timespecsub,
     timespecclear, timespecisset, timespeccmp — operations on time structure

LIBRARY

     Utility functions from BSD systems (libbsd, -lbsd)

SYNOPSIS

     #include <sys/time.h>
     (See libbsd(7) for include usage.)

     void
     timeradd(struct timeval *a, struct timeval *b, struct timeval *res);

     void
     timersub(struct timeval *a, struct timeval *b, struct timeval *res);

     void
     timerclear(struct timeval *tv);

     int
     timerisset(struct timeval *tv);

     int
     timercmp(struct timeval *a, struct timeval *b, CMP);

     void
     timespecadd(struct timespec *a, struct timespec *b, struct timespec *res);

     void
     timespecsub(struct timespec *a, struct timespec *b, struct timespec *res);

     void
     timespecclear(struct timespec *ts);

     int
     timespecisset(struct timespec *ts);

     int
     timespeccmp(struct timespec *a, struct timespec b, CMP);

DESCRIPTION

     These macros are provided for manipulating the timeval and timespec structures described in
     timeval(3bsd).

     The timeradd() and timespecadd() macros add the time information stored in a to b, storing
     the result in res.  With timeradd() the results are simplified such that the value of
     res->tv_usec is always less than 1,000,000 (1 second).  With timespecadd() the res->tv_nsec
     member of struct timespec is always less than 1,000,000,000.

     The timersub() and timespecsub() macros subtract the time information stored in b from a and
     store the resulting structure in res.

     The timerclear() and timespecclear() macros initialize the structures to midnight (0 hour)
     January 1st, 1970 (the Epoch).  In other words, they set the members of the structure to
     zero.

     The timerisset() and timespecisset() macros return true if the input structure is set to any
     time value other than the Epoch.

     The timercmp() and timespeccmp() macros compare a to b using the comparison operator given
     in CMP.  The result of the comparison is returned.

SEE ALSO

     timeval(3bsd)

HISTORY

     The timeradd() family of macros first appeared in NetBSD 1.1.  These were later ported to
     FreeBSD 2.2.6.  The timespec() family of macros first appeared in NetBSD 1.2.