INTRO (9) NetBSD Kernel Developer's Manual INTRO (9) NAME ...

TODR (9) NetBSD Kernel Developer’s Manual TODR (9)NAMEtodr_attach, todr_gettime, todr_settime, clock_ymdhms_to_secs,clock_secs_to_ymdhms —time-of-day clock supportSYNOPSIS#include voidtodr_attach(todr_chip_handle_t);inttodr_gettime(todr_chip_handle_t , struct timeval ∗);inttodr_settime(todr_chip_handle_t , struct timeval ∗);voidclock_secs_to_ymdhms(int , struct clock_ymdhms ∗);time_tclock_ymdhms_to_secs(struct clock_ymdhms ∗);DESCRIPTIONThe todr_∗() functions provide an interface to read, set and control time-of-day devices. A driver fora time-of-day device registers its todr_chip_handle_t with machine-dependent code using thetodr_attach() function. Alternatively, amachine-dependent front-end to a time-of-day device drivermay obtain the todr_chip_handle_t directly.The todr_gettime() retrieves the current data and time from the TODR device and returns it in thestruct timeval storage provided by the caller. todr_settime() sets the date and time in the TODRdevice 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 atime 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 {u_short 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.RETURN VALUESThe 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 invalidtodr_chip_handle_t is passed to any ofthese functions.The clock_ymdhms_to_secs() function returns −1 if the time in seconds would be less that zero or toolarge to fit in a time_t. The clock_secs_to_ymdhms() function never fails.NetBSD 3.0 September 6, 2006 1