NAME

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

LIBRARY

     library “libbsd”

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.