RTCWAKE(8) System Administration RTCWAKE(8) (NAME) rtcwake - RTC (SYNOPSIS) rtcwake [options] [-d device] [-m standby_mode] {-s seconds|-t time_t} (DESCRIPTION) . . RTC . apmsleep ACPI S1 ( standby) S3 ( suspend-to-RAM) . BIOS APM ACPI . nvram-wakeup ACPI S4 ( suspend to disk) . . RTC . USB Enter . rtcwake . (OPTIONS) -A, --adjfile file . -a, --auto ( UTC ) adjtime hwclock(8) . . --date timestamp (timestamp). timestamp : YYYYMMDDhhmmss "YYYY-MM-DD hh:mm:ss" "YYYY-MM-DD hh:mm" ( 00 ) YYYY-MM-DD ( 00:00:00 ) hh:mm:ss ( ) hh:mm ( 00 ) +number[smhd] (/// ) tomorrow ( 00:00:00 ) +number[smhd] : +5m +6h +2d. : +5min +6hours +2days. -d, --device device device rtc0 . RTC . rtc1 rtc2 ... . -l, --local adjtime . --list-modes --mode. -m, --mode mode (standby) . mode : standby ACPI S1. . . freeze (idle) . (Suspend-to-RAM) . ( 3.9 .) mem ACPI S3 ( Suspend-to-RAM). (self-refresh) . disk ACPI S4 ( Suspend-to-disk). . Suspend-to-RAM . off ACPI S5 ( Poweroff). '/sbin/shutdown' . ACPI . no RTC . on RTC . . disable . show : "alarm: off|on