TODR(9) | Kernel Developer's Manual | TODR(9) |
todr_attach
, todr_gettime
,
todr_settime
,
clock_ymdhms_to_secs
,
clock_secs_to_ymdhms
—
#include <dev/clock_subr.h>
void
todr_attach
(todr_chip_handle_t);
int
todr_gettime
(todr_chip_handle_t,
struct timeval *);
int
todr_settime
(todr_chip_handle_t,
struct timeval *);
int
clock_secs_to_ymdhms
(time_t,
struct clock_ymdhms
*);
time_t
clock_ymdhms_to_secs
(struct
clock_ymdhms *);
todr_*
() functions provide an interface to read, set
and control ‘time-of-day
’ devices. A
driver for a ‘time-of-day
’ device
registers its todr_chip_handle_t with machine-dependent
code using the todr_attach
() function. Alternatively,
a machine-dependent front-end to a
‘time-of-day
’ device driver may obtain
the todr_chip_handle_t directly.
The todr_gettime
() retrieves the current
data and time from the TODR device and returns it in the
struct timeval storage provided by the caller.
todr_settime
() sets the date and time in the TODR
device represented by todr_chip_handle_t according to
the struct timeval argument.
The utilities clock_secs_to_ymdhms
() and
clock_ymdhms_to_secs
() are provided to convert a
time value in seconds to and from a structure representing the date and time
as a ⟨year,month,day,weekday,hour,minute,seconds⟩ tuple. This
structure is defined as follows:
struct clock_ymdhms { uint64_t dt_year; /* Year */ u_char dt_mon; /* Month (1-12) */ u_char dt_day; /* Day (1-31) */ u_char dt_wday; /* Day of week (0-6) */ u_char dt_hour; /* Hour (0-23) */ u_char dt_min; /* Minute (0-59) */ u_char dt_sec; /* Second (0-59) */ };
Note: leap years are recognised by these conversion routines.
todr_*
() functions return 0 if the requested
operation was successful; otherwise an error code from
<sys/errno.h>
shall be
returned. However, behaviour is undefined if an invalid
todr_chip_handle_t is passed to any of these functions.
The clock_ymdhms_to_secs
() function
returns -1 if the time in seconds would be less that zero or too large to
fit in a time_t. The
clock_secs_to_ymdhms
() function returns 0 on success
or EINVAL
if the time passed is negative.
September 10, 2014 | NetBSD 9.0 |