gettimeofday(3C)					   Standard C Library Functions 					  gettimeofday(3C)

NAME

       gettimeofday, settimeofday - get or set the date and time

SYNOPSIS

       #include <sys/time.h>

       int gettimeofday(struct timeval *tp, void *tzp);

       int settimeofday(struct timeval *tp, void *tzp);

DESCRIPTION

       The  gettimeofday()  function  gets  and  the  settimeofday()  function	sets  the system's notion of the current time. The current time is
       expressed in elapsed seconds and microseconds since 00:00 Universal Coordinated Time, January 1, 1970. The resolution of the  system  clock
       is hardware dependent; the time may be updated continuously or in clock ticks.

       The tp argument points to a timeval structure, which includes the following members:

	 long	 tv_sec;    /* seconds since Jan. 1, 1970 */
	 long	 tv_usec;   /* and microseconds */

       If tp is a null pointer, the current time information is not returned or set.

       The TZ environment variable holds time zone information. See TIMEZONE(4).

       The tzp argument to gettimeofday() and settimeofday() is ignored.

       Only privileged processes can set the time of day.

RETURN VALUES

       Upon successful completion, 0 is returned.  Otherwise, -1 is returned and errno is set to indicate the error.

ERRORS

       The settimeofday() function will fail if:

       EINVAL	 The structure pointed to by tp specifies an invalid time.

       EPERM	 The {PRIV_SYS_TIME} privilege was not asserted in the effective set of the calling process.

       The gettimeofday() function will fail for 32-bit interfaces if:

       EOVERFLOW    The  system  time  has progressed beyond 2038, thus the size of the tv_sec member of the timeval structure pointed to by tp is
		    insufficient to hold the current time in seconds.

USAGE

       If the tv_usec member of tp is > 500000, settimeofday() rounds the seconds upward. If the time needs to be set with better than one  second
       accuracy, call settimeofday() for the seconds and then adjtime(2) for finer accuracy.

ATTRIBUTES

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

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |gettimeofday() is Standard.  |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       adjtime(2), ctime(3C), gethrtime(3C), TIMEZONE(4), attributes(5), privileges(5), standards(5)

SunOS 5.11							    1 Aug 2003							  gettimeofday(3C)