| .\" Copyright (c) 2007, SUSE LINUX Products GmbH |
| .\" Bernhard Walle <bwalle@suse.de> |
| .\" |
| .\" This program is free software; you can redistribute it and/or |
| .\" modify it under the terms of the GNU General Public License |
| .\" as published by the Free Software Foundation; either version 2 |
| .\" of the License, or (at your option) any later version. |
| .\" |
| .\" This program is distributed in the hope that it will be useful, |
| .\" but WITHOUT ANY WARRANTY; without even the implied warranty of |
| .\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| .\" GNU General Public License for more details. |
| .\" |
| .\" You should have received a copy of the GNU General Public License |
| .\" along with this program; if not, write to the Free Software |
| .\" Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| .\" 02110-1301, USA. |
| .\" |
| .TH RTCWAKE 8 "June 2015" "util-linux" "System Administration" |
| .SH NAME |
| rtcwake \- enter a system sleep state until specified wakeup time |
| .SH SYNOPSIS |
| .B rtcwake |
| [options] |
| .RB [ \-d |
| .IR device ] |
| .RB [ \-m |
| .IR standby_mode ] |
| .RB { "\-s \fIseconds\fP" | "\-t \fItime_t\fP" } |
| .SH DESCRIPTION |
| This program is used to enter a system sleep state and to automatically |
| wake from it at a specified time. |
| .PP |
| 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. |
| .PP |
| This is normally used like the old \fBapmsleep\fP 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. |
| .PP |
| On some systems, this can also be used like \fBnvram-wakeup\fP, waking from states |
| like ACPI S4 (suspend to disk). Not all systems have persistent media that are |
| appropriate for such suspend modes. |
| .PP |
| Note that alarm functionality depends on hardware; not every RTC is able to setup |
| an alarm up to 24 hours in the future. |
| .SH OPTIONS |
| .TP |
| .BR \-A , " \-\-adjfile " \fIfile |
| Specify an alternative path to the adjust file. |
| .TP |
| .BR \-a , " \-\-auto" |
| Read the clock mode (whether the hardware clock is set to UTC or local time) |
| from the \fIadjtime\fP file, where |
| .BR hwclock (8) |
| stores that information. This is the default. |
| .TP |
| .BR \-\-date " \fItimestamp" |
| Set the wakeup time to the value of the timestamp. Format of the |
| timestmap can be any of the following: |
| .TS |
| tab(|); |
| left l2 l. |
| 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 |
| .TE |
| .TP |
| .BR \-d , " \-\-device " \fIdevice |
| Use the specified \fIdevice\fP instead of \fBrtc0\fP as realtime clock. |
| This option is only relevant if your system has more than one RTC. |
| You may specify \fBrtc1\fP, \fBrtc2\fP, ... here. |
| .TP |
| .BR \-l , " \-\-local" |
| Assume that the hardware clock is set to local time, regardless of the |
| contents of the \fIadjtime\fP file. |
| .TP |
| .B \-\-list\-modes |
| List available \-\-mode option arguments. |
| .TP |
| .BR \-m , " \-\-mode " \fImode |
| Go into the given standby state. Valid values for \fImode\fP are: |
| .RS |
| .TP |
| .B 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. |
| .TP |
| .B 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.) |
| .TP |
| .B 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. |
| .TP |
| .B 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. |
| .TP |
| .B off |
| ACPI state S5 (Poweroff). This is done by calling '/sbin/shutdown'. |
| Not officially supported by ACPI, but it usually works. |
| .TP |
| .B no |
| Don't suspend, only set the RTC wakeup time. |
| .TP |
| .B on |
| Don't suspend, but read the RTC device until an alarm time appears. |
| This mode is useful for debugging. |
| .TP |
| .B disable |
| Disable a previously set alarm. |
| .TP |
| .B 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". |
| .RE |
| .TP |
| .BR \-n , " \-\-dry-run" |
| This option does everything apart from actually setting up the alarm, |
| suspending the system, or waiting for the alarm. |
| .TP |
| .BR \-s , " \-\-seconds " \fIseconds |
| Set the wakeup time to \fIseconds\fP in the future from now. |
| .TP |
| .BR \-t , " \-\-time " \fItime_t |
| Set the wakeup time to the absolute time \fItime_t\fP. \fItime_t\fP |
| is the time in seconds since 1970-01-01, 00:00 UTC. Use the |
| .BR date (1) |
| tool to convert between human-readable time and \fItime_t\fP. |
| .TP |
| .BR \-u , " \-\-utc" |
| Assume that the hardware clock is set to UTC (Universal Time Coordinated), |
| regardless of the contents of the \fIadjtime\fP file. |
| .TP |
| .BR \-v , " \-\-verbose" |
| Be verbose. |
| .TP |
| .BR \-V , " \-\-version" |
| Display version information and exit. |
| .TP |
| .BR \-h , " \-\-help" |
| Display help text and exit. |
| .SH NOTES |
| Some PC systems can't currently exit sleep states such as \fBmem\fP |
| using only the kernel code accessed by this driver. |
| They need help from userspace code to make the framebuffer work again. |
| .SH FILES |
| .I @ADJTIME_PATH@ |
| .SH 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. |
| .SH AUTHORS |
| The program was written by David Brownell <dbrownell@users.sourceforge.net> |
| and improved by Bernhard Walle <bwalle@suse.de>. |
| .SH COPYRIGHT |
| This is free software. You may redistribute copies of it under the terms |
| of the GNU General Public License <http://www.gnu.org/licenses/gpl.html>. |
| There is NO WARRANTY, to the extent permitted by law. |
| .SH "SEE ALSO" |
| .BR hwclock (8), |
| .BR date (1) |
| .SH AVAILABILITY |
| The rtcwake command is part of the util-linux package and is available from the |
| .UR https://\:www.kernel.org\:/pub\:/linux\:/utils\:/util-linux/ |
| Linux Kernel Archive |
| .UE . |