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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 fol-
       lowing 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 TIME-
       ZONE(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 sec-
       onds  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), priv-
       ileges(5), standards(5)

SunOS 5.10			  1 Aug	2003		      gettimeofday(3C)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | USAGE | ATTRIBUTES | SEE ALSO

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