freebsd-skq/usr.bin/backlight/backlight.8
Baptiste Daroussin 4d1308f49b backlight: accept '%' in the brightness input value
Improve friendlyness of the command line by accepting the percent brightness
in both format: with or without a trailing '%'

Reviewed by:	manu
Differential Revision:	https://reviews.freebsd.org/D26692
2020-10-06 08:05:19 +00:00

97 lines
2.7 KiB
Groff

.\" Copyright (c) 2020 Emmanuel Vadot <manu@freebsd.org>
.\"
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.\" $FreeBSD$
.\"
.Dd October 06, 2020
.Dt BACKLIGHT 8
.Os
.Sh NAME
.Nm backlight
.Nd configure backlight hardware
.Sh SYNOPSIS
.Nm
.Op Fl f Ar device
.Op Fl q
.Op Fl i
.Op Ar value
.Nm
.Op Fl f Ar device
incr | +
.Op Ar value
.Nm
.Op Fl f Ar device
decr | -
.Op Ar value
.Sh DESCRIPTION
The
.Nm
utility can be used to configure brightness levels for registered backlights
.Pp
The options are as follows:
.Bl -tag -width "-f device"
.It Fl f Ar device
Device to operate on.
If not specified,
.Pa /dev/backlight/backlight0
is used.
If an unqualified name is provided,
.Pa /dev/backlight
is automatically prepended.
.It Fl q
When querying the brightness level only print the value.
.It Fl i
Query information about the backlight (name, type).
.It Ar value
Set the brightness level to this value, must be between 0 and 100.
A trailing '%' is valid.
.It Ar incr | +
.Op Ar value
Decrement the backlight level.
If no value is specified a default of 10 percent is used.
.It Ar decr | -
.Op Ar value
Increment the backlight level.
If no value is specified a default of 10 percent is used.
.El
.Sh EXAMPLES
.Bl -bullet
.It
Show the current brightness level
.Bd -literal
backlight -f /dev/backlight/backlight0
.Ed
.El
.Sh SEE ALSO
.Xr backlight 9
.Sh HISTORY
The
.Nm
utility appeared in
.Fx 13.0 .
.Sh AUTHORS
.An -nosplit
The
.Nm
utility and this manual page were written by
.An Emmanuel Vadot Aq Mt manu@FreeBSD.org .