usr/src/boot/sys/boot/forth/delay.4th.8

.\" Copyright (c) 2011 Devin Teske
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.\" $FreeBSD$
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.Dd May 18, 2011
.Dt DELAY.4TH 8
.Os
.Sh NAME
.Nm delay.4th
.Nd FreeBSD debugging boot module
.Sh DESCRIPTION
The file that goes by the name of
.Nm
is a set of commands designed to add debugging capabilities to
.Xr loader 8 .
The commands of
.Nm
by themselves are not enough for most uses.
Please refer to the
examples below for the most common situations, and to
.Xr loader 8
for additional commands.
.Pp
Before using any of the commands provided in
.Nm ,
it must be included
through the command:
.Pp
.Dl include delay.4th
.Pp
This line is present in
.Pa /boot/beastie.4th
file, so it is not needed (and should not be re-issued) in a normal setup.
.Pp
The commands provided by it are:
.Pp
.Bl -tag -width disable-module_module -compact -offset indent
.It Ic delay_execute
Executes the [string] procedure stored in the
.Ic delay_command
environment variable after
.Ic loader_delay
seconds.
.Pp
If the optional
.Ic delay_showdots
environment variable is set, a continuous series of dots is printed.
.Pp
During the duration, the user can either press Ctrl-C (or Esc) to abort or
ENTER to proceed immediately.
.El
.Pp
The environment variables that effect its behavior are:
.Bl -tag -width bootfile -offset indent
.It Va delay_command
The command to be executed by
.Ic delay_execute .
.It Va loader_delay
The duration (in seconds) to delay before executing
.Ic delay_command .
.It Va delay_showdots
If set, will cause
.Ic delay_execute
to print a continuous series of dots during the delay duration.
.El
.Sh FILES
.Bl -tag -width /boot/loader.4th -compact
.It Pa /boot/loader
The
.Xr loader 8 .
.It Pa /boot/delay.4th
.Nm
itself.
.It Pa /boot/loader.rc
.Xr loader 8
bootstrapping script.
.El
.Sh EXAMPLES
Introducing a 5-second delay before including another file from
.Pa /boot/loader.rc :
.Pp
.Bd -literal -offset indent -compact
include /boot/delay.4th
set delay_command="include /boot/other.4th"
set delay_showdots
set loader_delay=5
delay_execute
.Ed
.Sh SEE ALSO
.Xr loader.conf 5 ,
.Xr beastie.4th 8 ,
.Xr loader 8 ,
.Xr loader.4th 8
.Sh HISTORY
The
.Nm
set of commands first appeared in
.Fx 9.0 .
.Sh AUTHORS
The
.Nm
set of commands was written by
.An -nosplit
.An Devin Teske Aq dteske@FreeBSD.org .