gettimeofday(3BSD) (BSD System Compatibility) gettimeofday(3BSD)
NAME
gettimeofday, settimeofday - (BSD) get or set the date and
time
SYNOPSIS
/usr/ucb/cc [flag . . . ] file . . .
#include <sys/time.h>
int gettimeofday(struct timeval *tp, struct timezone *tzp);
int settimeofday(struct timeval *tp, struct timezone *tzp);
DESCRIPTION
The system's notion of the current Greenwich time is obtained
with the gettimeofday call, and set with the settimeofday
call. The current time is expressed in elapsed seconds and
microseconds since 00:00 GMT, January 1, 1970 (zero hour).
The resolution of the system clock is hardware dependent; the
time may be updated continuously, or in ``ticks.''
tp 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.
tzp is an obsolete pointer formerly used to get and set time
zone information. tzp is now ignored. Time zone information
is now handled using the TZ environment variable; see
timezone(4).
Only the privileged user may set the time of day.
RETURN VALUE
A -1 return value indicates an error occurred; in this case an
error code is stored in the global variable errno.
ERRORS
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.
Copyright 1994 Novell, Inc. Page 1
gettimeofday(3BSD) (BSD System Compatibility) gettimeofday(3BSD)
REFERENCES
adjtime(2), ctime(3C), date(1), gettimeofday(2), timezone(4)
NOTICES
Time is never correct enough to believe the microsecond
values.
tzp is ignored.
Copyright 1994 Novell, Inc. Page 2