init(8)init(8)Nameinit - process control initialization
Syntax
/bin/init
Description
The ULTRIX system invokes the command as the last step in the boot pro‐
cedure. The system normally then runs the automatic reboot sequence,
as described in If succeeds, begins multiuser operation. If fails,
begins single-user operation by giving the superuser a shell on the
console.
You can use the BOOT command so that parameters are passed from the
boot program to so that multiuser operation begins immediately. When
the superuser terminates the single-user shell (by pressing CTRL/D),
runs the command file without the reboot parameter. This command file
performs housekeeping operations such as removing temporary files,
mounting file systems, and starting daemons. For further information,
see
In multiuser operation, creates a process for each terminal port where
a user may log in. To begin such operations, it reads the file. For
further information, see For each terminal that is marked ``on'' in the
file, forks and invokes the command specified for the current line.
The command is passed the name of the terminal as the last argument.
The other arguments (if any) are specified after the command in the
file. Usually, the command is but it may be any command.
The command reads the user's name and invokes the command to log in the
user and execute the shell.
Ultimately, the shell terminates because of an end-of-file. The end-
of-file may be typed explicitly or generated as a result of hanging up
on a terminal line. The main path of the command, which has been wait‐
ing for such an event, wakes up and removes the appropriate entry from
the file, which records current users. The command then makes an entry
in which maintains a history of logins and logouts. The entry is made
only if a user logged in successfully on the line. Then the appropri‐
ate terminal is reopened and is reinvoked.
The command catches the signal (signal SIGHUP) and interprets it to
mean that the file should be read again. The shell process on each
line which was active in the file but is no longer there is terminated;
a new process is created for each added line; lines unchanged in the
file are undisturbed. Thus, it is possible to drop or add phone lines
without rebooting the system by changing the file and sending a signal
to the process, using the kill -HUP 1 command.
If the line in the file for the X server has changed since the last
time the X server was started, issuing the kill -HUP 1 command restarts
the X server. Users are logged out and must log in again.
The command terminates multiuser operations and resumes single-user
mode if it receives a terminate (TERM) signal. That is, the superuser
types kill -TERM 1. If there are processes outstanding which are dead‐
locked (due to hardware or software failure), does not wait for them
all to die, but times out after 30 seconds and prints a warning mes‐
sage.
If receives a terminal stop signal (the superuser types kill -TSTP 1),
stops creating new processes and lets the system slowly die away. A
later hangup will resume full multiuser operations, or a terminate will
initiate a single user shell. This feature is used by and
If dies, the system reboots itself automatically. If, at bootstrap
time, the process cannot be located, the system loops in user mode at
location 0x13.
Diagnostics
WARNING: Something is hung (wont die); ps axl advised
The system is shutting down, and cannot kill a certain process. This
usually occurs when a process cannot exit a device driver due to a per‐
sistent device error condition.
init: `command tty' failing, sleeping
The command tried to spawn a new process (use the system call) for the
command five times. Each time, the command failed. This may indicate
that the command was invoked with invalid arguments. Check the file
for errors. This error message is printed at level LOG_ERR.
init: exec failed: cmd= command reason
The command tried to spawn a new process using the system call for the
command. The failed. The reason is the explanation produced by the
routine for why the failed. This error message is printed at level
LOG_ERR.
Files
List of current system users
History of logins and logouts
The command reads this file for a command to execute for the
terminal line
Command file executed by
See Alsottys(5), getty(8), rc(8), reboot(8)
VAX init(8)
