timeradd(3C)						   Standard C Library Functions 					      timeradd(3C)

NAME

       timeradd, timersub, timerclear, timerisset, timercmp - operations on timeval structures

SYNOPSIS

       #include <sys/time.h>

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

       void timerclear(struct timeval *tvp);

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

       int timerisset(struct timeval *tvp);

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

DESCRIPTION

       These macros are provided for manipulating timeval structures for use with gettimeofday(3C) and settimeofday(3C) operands. The structure is
       defined in <sys/time.h> as:

	 struct timeval {
	     long    tv_sec;	 /* seconds since Jan. 1, 1970 */
	     long    tv_usec;	 /* and microseconds */
	 };

       The timeradd() macro adds the time information stored in a to b and stores the resulting timeval in res. The results  are  simplified  such
       that the value of res->tv_usec is always less than 1,000,000 (1 second).

       The timersub() macro subtracts the time information stored in b from a and stores the resulting timeval in res.

       The timerclear() macro initializes tvp to midnight (0 hour) January 1st, 1970 (the Epoch).

       The timerisset() macro returns true if tvp is set to any time value other than the Epoch.

       The timercmp() macro compares a to b using the form a CMP b, where CMP is one of <, <=, ==, !=, >=, or >.

USAGE

       These macros are not available in function form. All of these macros evaluate their arguments more than once. If parameters passed to these
       macros are expressions with side effects, the results are undefined.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Committed 		   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe with Exceptions	   |
       +-----------------------------+-----------------------------+

SEE ALSO

       gettimeofday(3C), attributes(5)

SunOS 5.11							    12 Jun 2008 						      timeradd(3C)