//po4a: entry man manual = rtcwake(8) :doctype: manpage :man manual: System Administration :man source: util-linux {release-version} :page-layout: base :command: rtcwake == NAME rtcwake - enter a system sleep state until specified wakeup time == SYNOPSIS *rtcwake* [options] [*-d* _device_] [*-m* _standby_mode_] {*-s* _seconds_|*-t* _time_t_} == DESCRIPTION This program is used to enter a system sleep state and to automatically wake from it at a specified time. This uses cross-platform Linux interfaces to enter a system sleep state, and leave it no later than a specified time. It uses any RTC framework driver that supports standard driver model wakeup flags. This is normally used like the old *apmsleep* utility, to wake from a suspend state like ACPI S1 (standby) or S3 (suspend-to-RAM). Most platforms can implement those without analogues of BIOS, APM, or ACPI. On some systems, this can also be used like *nvram-wakeup*, waking from states like ACPI S4 (suspend to disk). Not all systems have persistent media that are appropriate for such suspend modes. Note that alarm functionality depends on hardware; not every RTC is able to setup an alarm up to 24 hours in the future. The suspend setup may be interrupted by active hardware; for example wireless USB input devices that continue to send events for some fraction of a second after the return key is pressed. *rtcwake* tries to avoid this problem and it waits to the terminal to settle down before entering a system sleep. == OPTIONS *-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: [cols=",",] |=== |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