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diff --git a/sys-utils/rtcwake.8.adoc b/sys-utils/rtcwake.8.adoc new file mode 100644 index 0000000..481a586 --- /dev/null +++ b/sys-utils/rtcwake.8.adoc @@ -0,0 +1,142 @@ +//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 <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. + +include::man-common/help-version.adoc[] + +== NOTES + +Some PC systems can't currently exit sleep states such as *mem* using only the kernel code accessed by this driver. They need help from userspace code to make the framebuffer work again. + +== FILES + +_{ADJTIME_PATH}_ + +== HISTORY + +The program was posted several times on LKML and other lists before appearing in kernel commit message for Linux 2.6 in the GIT commit 87ac84f42a7a580d0dd72ae31d6a5eb4bfe04c6d. + +== AUTHORS + +The program was written by mailto:dbrownell@users.sourceforge.net[David Brownell] and improved by mailto:bwalle@suse.de[Bernhard Walle]. + +== COPYRIGHT + +This is free software. You may redistribute copies of it under the terms of the link:http://www.gnu.org/licenses/gpl.html[GNU General Public License]. There is NO WARRANTY, to the extent permitted by law. + +== SEE ALSO + +*adjtime_config*(5), +*hwclock*(8), +*date*(1) + +include::man-common/bugreports.adoc[] + +include::man-common/footer.adoc[] + +ifdef::translation[] +include::man-common/translation.adoc[] +endif::[] |