System administration command. Read or set the hardware clock. This command maintains change information in /etc/adjtime,
which can be used to adjust the clock based on how much it drifts over time. hwclock replaces the clock command. The single-letter
options are included for compatibility with the older command.
Linux Commad Options:
You may specify only one of the following options: -a, --adjust
Adjust the hardware clock based on information in /etc/adjtime and set the system clock to the new time. --getepoch
Print the kernel’s hardware clock epoch value, then exit. -r, --show
Print the current time stored in the hardware clock. -s, --hctosys
Set the system time in accordance with the hardware clock. --setepoch, --epoch=year
Set the hardware clock’s epoch to year. --set --date=date
Set the hardware clock to the specified date, a string appropriate for use with the date command. -v, --version
Print version and exit. -w, --systohc
Set the hardware clock in accordance with the system time. The following may be used with the above options: --debug
Print information about what hwclock is doing. --localtime
The hardware clock is stored in local time. --noadjfile
Disable /etc/adjtime facilities. --test
Do not actually change anything. This is good for checking syntax. -u, --utc
The hardware clock is stored in Universal Coordinated Time.
