-A, --adjfile file
Specify an alternative path to the adjust file.
-a, --auto
Read the clock mode (whether the hardware clock is set to UTC
or local time) from the adjtime file, where hwclock(8) stores
that information. This is the default.
--date timestamp
Set the wakeup time to the value of the timestamp. Format of
the timestamp can be any of the following:
┌────────────────────┬─────────────────────────┐
│ │ │
│YYYYMMDDhhmmss │ │
├────────────────────┼─────────────────────────┤
│ │ │
│YYYY-MM-DD hh:mm:ss │ │
├────────────────────┼─────────────────────────┤
│ │ │
│YYYY-MM-DD hh:mm │ (seconds will be set to │
│ │ 00) │
├────────────────────┼─────────────────────────┤
│ │ │
│YYYY-MM-DD │ (time will be set to │
│ │ 00:00:00) │
├────────────────────┼─────────────────────────┤
│ │ │
│hh:mm:ss │ (date will be set to │
│ │ today) │
├────────────────────┼─────────────────────────┤
│ │ │
│hh:mm │ (date will be set to │
│ │ today, seconds to 00) │
├────────────────────┼─────────────────────────┤
│ │ │
│tomorrow │ (time is set to │
│ │ 00:00:00) │
├────────────────────┼─────────────────────────┤
│ │ │
│+5min │ │
└────────────────────┴─────────────────────────┘
-d, --device device
Use the specified device instead of rtc0 as realtime clock.
This option is only relevant if your system has more than one
RTC. You may specify rtc1, rtc2, ... here.
-l, --local
Assume that the hardware clock is set to local time,
regardless of the contents of the adjtime file.
--list-modes
List available --mode option arguments.
-m, --mode mode
Go into the given standby state. Valid values for mode are:
standby
ACPI state S1. This state offers minimal, though real,
power savings, while providing a very low-latency
transition back to a working system. This is the default
mode.
freeze
The processes are frozen, all the devices are suspended
and all the processors idled. This state is a general
state that does not need any platform-specific support,
but it saves less power than Suspend-to-RAM, because the
system is still in a running state. (Available since
Linux 3.9.)
mem
ACPI state S3 (Suspend-to-RAM). This state offers
significant power savings as everything in the system is
put into a low-power state, except for memory, which is
placed in self-refresh mode to retain its contents.
disk
ACPI state S4 (Suspend-to-disk). This state offers the
greatest power savings, and can be used even in the
absence of low-level platform support for power
management. This state operates similarly to
Suspend-to-RAM, but includes a final step of writing
memory contents to disk.
off
ACPI state S5 (Poweroff). This is done by calling
'/sbin/shutdown'. Not officially supported by ACPI, but
it usually works.
no
Don't suspend, only set the RTC wakeup time.
on
Don't suspend, but read the RTC device until an alarm
time appears. This mode is useful for debugging.
disable
Disable a previously set alarm.
show
Print alarm information in format: "alarm: off|on
<time>". The time is in ctime() output format, e.g.,
"alarm: on Tue Nov 16 04:48:45 2010".
-n, --dry-run
This option does everything apart from actually setting up
the alarm, suspending the system, or waiting for the alarm.
-s, --seconds seconds
Set the wakeup time to seconds in the future from now.
-t, --time time_t
Set the wakeup time to the absolute time time_t. time_t is
the time in seconds since 1970-01-01, 00:00 UTC. Use the
date(1) tool to convert between human-readable time and
time_t.
-u, --utc
Assume that the hardware clock is set to UTC (Universal Time
Coordinated), regardless of the contents of the adjtime file.
-v, --verbose
Be verbose.
-V, --version
Display version information and exit.
-h, --help
Display help text and exit.
