xref: /netbsd/usr.sbin/screenblank/screenblank.1 (revision 21aac92a)

.\"	$NetBSD: screenblank.1,v 1.18 2019/04/08 20:18:14 sevan Exp $
.\"
.\" Copyright (c) 1996-2002 The NetBSD Foundation, Inc.
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.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Jason R. Thorpe.
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.Dd April 8, 2019
.Dt SCREENBLANK 1
.Os
.Sh NAME
.Nm screenblank
.Nd screen saver daemon for wscons and FBIO machines
.Sh SYNOPSIS
.Nm screenblank
.Op Fl k | Fl m
.Op Fl d Ar inactivity-timeout
.Op Fl e Ar wakeup-delay
.Op Fl f Ar framebuffer
.Op Fl i Ar input-device
.Nm
.Brq Fl b | Fl u
.Sh DESCRIPTION
.Nm
disables the framebuffer if the keyboard and mouse are idle for a period
of time, and re-enables the framebuffer when keyboard or mouse activity
resumes.
.Pp
When killed with a SIGINT, SIGHUP, or SIGTERM,
.Nm
will re-enable the framebuffer.
The pid can be found in the file
.Pa /var/run/screenblank.pid .
.Pp
The options are as follows:
.Bl -tag -width indent
.It Fl b
Overriding the other options, simply try (once) to blank the
framebuffer, then exit.
.It Fl d Ar inactivity-timeout
Wait the number of seconds specified by
.Ar inactivity-timeout ,
expressed in the format
.Dq xxx.xxx ,
before disabling the framebuffer due to inactivity.
The default is 600 seconds (10 minutes).
.It Fl e Ar wakeup-delay
Wait the number of seconds specified by
.Ar wakeup-delay ,
expressed in the format
.Dq xxx.xxx ,
before re-enabling the framebuffer once activity resumes.
The default is .25 seconds.
.It Fl f Ar framebuffer
Use the framebuffer device
.Ar framebuffer
instead of the default
.Pa /dev/fb .
.It Fl i Ar input-device
Add
.Ar input-device
to the list of devices to monitor for activity.
.It Fl k
Do not check the keyboard for activity.
.It Fl m
Do not check the mouse for activity.
.It Fl u
Overriding the other options, simply try (once) to unblank the
framebuffer, then exit.
.El
.Pp
Note that the
.Fl k
and
.Fl m
flags are mutually exclusive.
.Sh FILES
.Bl -tag -width "/var/run/screenblank.pid  "
.It /dev/kbd
The keyboard device.
.It /dev/mouse
The mouse device.
.It /dev/console
The console device.
.It /dev/fb
The default framebuffer.
.It /dev/wskbd
The keyboard for wscons machines.
.It /dev/wsmouse
The mouse device for wscons machines.
.It /dev/ttyE0
The console device for wscons machines.
.It /var/run/screenblank.pid
File containing the pid of
.Nm .
.El
.Sh CAVEATS
.Nm
checks the access and modification times of the devices it is
monitoring to determine activity.
If the devices are on a file system mounted with the
.Cm noatime
and/or
.Cm nodevmtime
options, it will not function as expected.
A possible workaround is to use a script as such:
.Bd -literal -offset indent
#!/bin/sh
/usr/sbin/screenblank -d 0 -e 0 && read
/usr/bin/pkill screenblank
.Ed