gettimeofday(3C)                                           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);

DESCRIPTION
     gettimeofday() gets and settimeofday() 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.

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

     long    tvsec;    /* seconds since Jan. 1, 1970 */
     long    tvusec;   /* and microseconds */

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

     tzp is an obsolete pointer formerly used to get and set timezone
     information. tzp is now ignored. Timezone information is now handled
     using the TZ environment variable [see timezone(4)].

     Only the privileged user may set the time of day.

RESULT
     A -1 return value indicates that an error occurred and errno has been
     set. The following error codes may be set in errno:

     EINVAL   tp specifies an invalid time.

     EPERM    A user other than the privileged user attempted to set the
              time or time zone.

NOTES
     The implementation of settimeofday() ignores the tvusec field of tp.
     If the time needs to be set with better than one second accuracy, call
     settimeofday() for the seconds and then adjtime for finer accuracy.

SEE ALSO
     adjtime(2), ctime(3C), timezone(4).







Page 1                       Reliant UNIX 5.44                Printed 11/98