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gettimeofday(2)						       gettimeofday(2)

       gettimeofday, settimeofday - get	or set date and	time

       #include	<sys/time.h>

       gettimeofday(tp,	tzp)
       struct timeval *tp;
       struct timezone *tzp;

       settimeofday(tp,	tzp)
       struct timeval *tp;
       struct timezone *tzp;

       The  system  call  returns the system's notion of the current Greenwich
       time and	the current time zone.	Time returned is expressed relative in
       seconds and microseconds	since midnight January 1, 1970.

       The structures pointed to by tp and tzp are defined in <sys/time.h> as:

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

       struct  timezone	 {	 int  tz_minuteswest;	  /*  of  Greenwich */
	    int	 tz_dsttime;	/* type	of dst correction to apply */ };

       The timezone structure indicates	the local time zone (measured in  min-
       utes  of	 time  westward	 from Greenwich), and a	flag that, if nonzero,
       indicates that Daylight Saving time applies locally during  the	appro-
       priate part of the year.

       Only the	superuser can set the time of day.

Return Values
       A  0 return value indicates that	the call succeeded.  A -1 return value
       indicates an error occurred, and	in this	case an	error code  is	stored
       into the	global variable	errno.

       The call	fails under the	following conditions:

       [EFAULT]	      An argument address referenced invalid memory.

       [EPERM]	      A	 user  other  than  the	superuser attempted to set the

See Also
       date(1),	stime(2), ctime(3)


Name | Syntax | Description | Return Values | Diagnostics | See Also

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