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Diffstat (limited to 'sys-utils/rtcwake.8')
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diff --git a/sys-utils/rtcwake.8 b/sys-utils/rtcwake.8 new file mode 100644 index 0000000..0972ff7 --- /dev/null +++ b/sys-utils/rtcwake.8 @@ -0,0 +1,189 @@ +.\" 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. +.PP +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. +.B rtcwake +tries to avoid this problem and it waits to terminal to settle down before +entering a system sleep. + +.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 +timestamp can be any of the following: +.TS +tab(|); +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 /etc/adjtime +.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 . |