[SOLVED] "shutdown -h +120 & 2&>1 > /dev/null". how to hide shutdown output ?
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user@host:~/Desktop# shutdown -h +120 2&>1 > /dev/null &
Broadcast message from user@host (pts/0) (Sun Nov 15 15:39:58 2015):
The system is going DOWN for system halt in 120 minutes!
+ Running shutdown -h +120 2 &>1 > /dev/null &
doesn't work either.
It returns with the warning.
And no help with "shutdown --help" about the output of the command.
user@host:~/Desktop# shutdown --help
shutdown: invalid option -- '-'
Usage: shutdown [-akrhPHfFnc] [-t sec] time [warning message]
-a: use /etc/shutdown.allow
-k: don't really shutdown, only warn.
-r: reboot after shutdown.
-h: halt after shutdown.
-P: halt action is to turn off power.
-H: halt action is to just halt.
-f: do a 'fast' reboot (skip fsck).
-F: Force fsck on reboot.
-n: do not go through "init" but go down real fast.
-c: cancel a running shutdown.
-t secs: delay between warning and kill signal.
** the "time" argument is mandatory! (try "now") **
^ what linux distro/version are you using?
on my systems (on archlinux & debian stable shutdown is part of systemd):
shutdown [OPTIONS...] [TIME] [WALL...]
Shut down the system.
--help Show this help
-H --halt Halt the machine
-P --poweroff Power-off the machine
-r --reboot Reboot the machine
-h Equivalent to --poweroff, overridden by --halt
-k Don't halt/power-off/reboot, just send warnings
--no-wall Don't send wall message before halt/power-off/reboot
-c Cancel a pending shutdown
SHUTDOWN(8) Linux System Administrator's Manual SHUTDOWN(8)
shutdown - bring the system down
/sbin/shutdown [-akrhPHfFnc] [-t sec] time [warning message]
shutdown brings the system down in a secure way. All logged-in users are notified that the system is going down, and login(1) is
blocked. It is possible to shut the system down immediately or after a specified delay. All processes are first notified that the
system is going down by the signal SIGTERM. This gives programs like vi(1) the time to save the file being edited, mail and news
processing programs a chance to exit cleanly, etc. shutdown does its job by signalling the init process, asking it to change the
runlevel. Runlevel 0 is used to halt the system, runlevel 6 is used to reboot the system, and runlevel 1 is used to put to system
into a state where administrative tasks can be performed; this is the default if neither the -h or -r flag is given to shutdown. To
see which actions are taken on halt or reboot see the appropriate entries for these runlevels in the file /etc/inittab.
-a Use /etc/shutdown.allow.
-k Don't really shutdown; only send the warning messages to everybody.
-r Reboot after shutdown.
-h Halt or power off after shutdown.
-P Halt action is to turn off the power.
-H Modifier to the -h flag. Halt action is to halt or drop into boot monitor on systems that support it. Must be used with the
-f Skip fsck on reboot.
-F Force fsck on reboot.
-n [DEPRECATED] Don't call init(8) to do the shutdown but do it ourself. The use of this option is discouraged, and its results
are not always what you'd expect.
-c Cancel a waiting shutdown. ("shutdown now" is no longer waiting.) With this option it is of course not possible to give the
time argument, but you can enter explanatory message arguments on the command line that will be sent to all users.
-t sec Tell init(8) to wait sec seconds between sending processes the warning and the kill signal, before changing to another run‐
time When to shutdown.
Message to send to all users.
The time argument can have different formats. First, it can be an absolute time in the format hh:mm, in which hh is the hour (1 or
2 digits) and mm is the minute of the hour (in two digits). Second, it can be in the format +m, in which m is the number of minutes
to wait. The word now is an alias for +0.
If shutdown is called with a delay, it will create the advisory file /etc/nologin which causes programs such as login(1) to not
allow new user logins. This file is created five minutes before the shutdown sequence starts. Shutdown removes this file if it is
stopped before it can signal init (i.e. it is cancelled or something goes wrong). It also removes it before calling init to change
The -f flag means `reboot fast'. This only creates an advisory file /fastboot which can be tested by the system when it comes up
again. The boot rc file can test if this file is present, and decide not to run fsck(1) since the system has been shut down in the
proper way. After that, the boot process should remove /fastboot.
The -F flag means `force fsck'. This only creates an advisory file /forcefsck which can be tested by the system when it comes up
again. The boot rc file can test if this file is present, and decide to run fsck(1) with a special `force' flag so that even prop‐
erly unmounted file systems get checked. After that, the boot process should remove /forcefsck.
The -n flag causes shutdown not to call init, but to kill all running processes itself. shutdown will then turn off quota, account‐
ing, and swapping and unmount all file systems.
shutdown can be called from init(8) when the magic keys CTRL-ALT-DEL are pressed, by creating an appropriate entry in /etc/inittab.
This means that everyone who has physical access to the console keyboard can shut the system down. To prevent this, shutdown can
check to see if an authorized user is logged in on one of the virtual consoles. If shutdown is called with the -a argument (add this
to the invocation of shutdown in /etc/inittab), it checks to see if the file /etc/shutdown.allow is present. It then compares the
login names in that file with the list of people that are logged in on a virtual console (from /var/run/utmp). Only if one of those
authorized users or root is logged in, it will proceed. Otherwise it will write the message
shutdown: no authorized users logged in
to the (physical) system console. The format of /etc/shutdown.allow is one user name per line. Empty lines and comment lines (pre‐
fixed by a #) are allowed. Currently there is a limit of 32 users in this file.
Note that if /etc/shutdown.allow is not present, the -a argument is ignored.
HALT OR POWEROFF
The -H option just sets the init environment variable INIT_HALT to HALT, and the -P option just sets that variable to POWEROFF. The
shutdown script that calls halt(8) as the last thing in the shutdown sequence should check these environment variables and call
halt(8) with the right options for these options to actually have any effect. Debian 3.1 (sarge) supports this.
A lot of users forget to give the time argument and are then puzzled by the error message shutdown produces. The time argument is
mandatory; in 90 percent of all cases this argument will be the word now.
Init can only capture CTRL-ALT-DEL and start shutdown in console mode. If the system is running the X window System, the X server
processes all key strokes. Some X11 environments make it possible to capture CTRL-ALT-DEL, but what exactly is done with that event
depends on that environment.
Shutdown wasn't designed to be run setuid. /etc/shutdown.allow is not used to find out who is executing shutdown, it ONLY checks who
is currently logged in on (one of the) console(s).
Miquel van Smoorenburg, email@example.com
fsck(8), init(8), halt(8), poweroff(8), reboot(8)
November 12, 2003 SHUTDOWN(8)
no xy-problem here.
I just want to leave the pc open when i go to sleep
and run a shutdown after one or two hours.
It is just strange to me why i can not hide the output
of the shutdown command, while i can do this with others commands...
The message sent by shutdown is broadcast to all logged-in users. It does not use stdout or stderr, so redirecting those won't affect that message. If your version of shutdown lacks the "--no-wall" option, you can't avoid the message, but perhaps you can use something like "(sleep 2h && init 0) &" to simulate the actions of shutdown. (I have no idea whether "init 0" still works with systemd.)
just return to OP: the command was not well constructed: shutdown -h +120 >/dev/null 2&>1
would be the correct on, but obviously that will not work too, because shutdown does not write directly to stdout/stderr but sends a broadcast message to all of the available terminals. You cannot hide it with redirection. http://unix.stackexchange.com/questi...adcast-message