.\" Copyright (c) 1980, 1991 Regents of the University of California.
.\" %sccs.include.redist.roff%
.\" @(#)init.8 6.4 (Berkeley) %G%
.Nd process control initialization
is the last stage of the boot process.
It normally runs the automatic reboot sequence as described in
and if this succeeds, begins multi-user operation.
If the reboot fails, it commences single user operation by giving
the super-user a shell on the console.
prevent the system from going multi-user and to instead execute
a single user shell with out starting the normal daemons.
The system is then quiescent for maintenance work and may
later be made it go multi-user by killing the
the single-user shell (with ^D).
start up command file without the reboot parameter.
processes for the terminal ports found in the file
reads this file, and executes the command found in the second field.
opens and initializes the tty line
program, when a valid user logs in,
exectutes a shell for that user. When this shell
dies, either because the user logged out
or an abnormal termination occured (a signal),
program wakes up, deletes the user
file of current users and records the logout in the
Lines may be added or deleted from the
file without a reboot by sending the signal
Upon receipt of this signal,
and if an engaged port has been deleted from the
file, it will only become inactive after the engaging process has
terminated (the user has logged off).
If a port is inactive (only a
or terminated processes are attached to it)
elimiates these processes.
For these ports and any new ports, for which a command is found
will terminate multi-user operations and resume single-user mode
If there are processes outstanding which are deadlocked (due to
hardware or software failure),
will not wait for them all to die (which might take forever), but
will time out after 30 seconds and print a warning message.
and allow the system to slowly die away, if it is sent a terminal stop
A later hangup will resume full
multi-user operations, or a terminate will initiate a single user shell.
is so critical that if it dies, the system will reboot itself
If, at bootstrap time, the
process cannot be located, the system will loop in user mode at location
.It "/usr/libexec/getty \\*(eMgettyargs\\*(fP failing, sleeping."
A process being started to service a line is exiting quickly
This is often caused by a ringing or noisy terminal line.
.Em "Init will sleep for 30 seconds" ,
.Em "then continue trying to start the process" .
.It "WARNING: Something is hung (wont die); ps axl advised."
is hung and could not be killed when the system was shutting down.
This is usually caused by a process
which is stuck in a device driver due to a persistent device error condition.
.Bl -tag -width /var/log/wtmp -compact
Record of Current users on the system.
Record of all logins and logouts.
The terminal initialization information file.