rc(8)

NAME

rc - command scripts for system startup

SYNOPSIS

/etc/rc
/etc/rc.local
/etc/rc.securelevel

DESCRIPTION

rc is the command script that is invoked by init(8) during

an automatic
reboot and after single user mode is exited; it performs

system house
keeping chores and starts up system daemons. Additionally,

rc is intri
cately tied to the netstart(8) script, which runs commands

and daemons
pertaining to the network. The rc.securelevel and rc.local

scripts hold
commands which are pertinent only to a specific site.

All four of these startup scripts are (or can be) controlled

to some
extent by variables defined in rc.conf(8) and rc.conf.lo

cal(8), which
specify which daemons and services to run.

When an automatic reboot is in progress, rc is invoked with

the argument
autoboot. The first portion of rc runs an fsck(8) with op

tion -p to
``preen'' all disks of minor inconsistencies resulting from

the last sys
tem shutdown and to check for serious inconsistencies caused

by hardware
or software failure. If this auto-check and repair suc

ceeds, then the
second part of rc is run.

However, if the file /fastboot exists, fsck(8) will not be

invoked during
this boot. This file is then removed so that it will be run

on subse
quent boots.

The second part of rc, which is run after an auto-reboot

succeeds and
also if rc is invoked when a single user shell terminates

(see init(8)),
then asks rc.conf(8) for configuration variables, mounts

filesystems,
starts system daemons, preserves editor files, clears the

scratch direc
tory /tmp, and saves any possible core image that might have

been gener
ated as a result of a system crash, with savecore(8).

Before rc starts most system daemons, netstart(8) is execut

ed.

rc.securelevel is executed by rc to start daemons that must

be run before
the security level changes. Following this, rc then sets

the security
level to the value specified in the securelevel variable in

that file.
See securelevel(7) for the effects of setting the security

level.

rc.local is executed towards the end of rc (it is not the

very last as
there are a few services that must be started at the very

end). Nor
mally, rc.local contains commands and daemons that are not

part of the
stock installation.

CONFIGURATION EXAMPLES

The rc.conf(8) file contains a series of Bourne-shell syntax

assignments
that are used to configure kernel configurations, network

configuration,
and various other system daemons. As described above, this

file is
sourced (using sh(1) of course) by /etc/rc. Various com

ments in
rc.conf(8) make it clear what each variable does. Refer to

the specific
man pages for each daemon to determine what that subsystem

does.

For example, the lpd(8) daemon is controlled by the follow

ing line:

lpd_flags=NO # for normal use: "" (or "-l" for

debugging)

This does not start lpd(8) at system startup. To start

lpd(8), the fol
lowing entry can be used:

lpd_flags="" # for normal use: "" (or "-l" for

debugging)

Alternately, lpd(8) can be started with the -l flag (to log

remote con
nections):

lpd_flags="-l" # for normal use: "" (or "-l" for

debugging)

EXTERNAL INFLUENCES

Before init(8) starts rc, it sets the process priority,

umask, and
resource limits according to the ``daemon'' login class as

described in
login.conf(5).

FILES

/etc/rc Command scripts for system startup.
/etc/rc.local Site specific command scripts for

system startup.
/etc/rc.conf System daemon configuration database.
/etc/rc.conf.local Site specific daemon configuration

database.
/etc/rc.securelevel Commands run before the security lev

el changes.
/etc/rc.shutdown Commands run at system shutdown.
/etc/login.conf Login class capability database.
/etc/netstart Command script for network startup.

SEE ALSO

login.conf(5), sysctl.conf(5), securelevel(7), init(8), net

start(8),
rc.conf(8), rc.shutdown(8), reboot(8), savecore(8)

HISTORY

The rc command appeared in 4.0BSD.

BSD December 11, 1993

BSD