init(8) [v7 man page]

INIT(8) 						      System Manager's Manual							   INIT(8)

NAME

       init, rc  -  process control initialization

SYNOPSIS

       /etc/init
       /etc/rc

DESCRIPTION

       Init  is  invoked  as  the last step of the boot procedure (see boot(8)).  Generally its role is to create a process for each typewriter on
       which a user may log in.

       When init first is executed the console typewriter /dev/console.  is opened for reading and writing and the shell is  invoked  immediately.
       This  feature  is used to bring up a single-user system.  If the shell terminates, init comes up multi-user and the process described below
       is started.

       When init comes up multiuser, it invokes a shell, with input taken from the file /etc/rc.  This command	file  performs	housekeeping  like
       removing temporary files, mounting file systems, and starting daemons.

       Then  init  reads  the file /etc/ttys and forks several times to create a process for each typewriter specified in the file.  Each of these
       processes opens the appropriate typewriter for reading and writing.  These channels thus receive file descriptors 0, 1 and 2, the  standard
       input,  output  and  error  files.   Opening  the typewriter will usually involve a delay, since the open is not completed until someone is
       dialed up and carrier established on the channel.  Then /etc/getty is called with argument as specified by the last character of  the  ttys
       file line.  Getty reads the user's name and invokes login(1) to log in the user and execute the shell.

       Ultimately  the	shell  will  terminate because of an end-of-file either typed explicitly or generated as a result of hanging up.  The main
       path of init, which has been waiting for such an event, wakes up and removes the appropriate entry from the file utmp, which  records  cur-
       rent  users,  and  makes  an  entry  in /usr/adm/wtmp, which maintains a history of logins and logouts.	Then the appropriate typewriter is
       reopened and getty is reinvoked.

       Init catches the hangup signal SIGHUP and interprets it to mean that the system should be brought from multi  user  to  single  user.   Use
       `kill -1 1' to send the hangup signal.

FILES

       /dev/tty?, /etc/utmp, /usr/adm/wtmp, /etc/ttys, /etc/rc

SEE ALSO

       login(1), kill(1), sh(1), ttys(5), getty(8)

																	   INIT(8)

init(8) 						      System Manager's Manual							   init(8)

Name
       init - process control initialization

Syntax
       /bin/init [ options ]

Description
       The ULTRIX system invokes the command as the last step in the boot procedure.  The system normally then runs the automatic reboot sequence,
       as described in If succeeds, the command begins multiuser operation.  If fails, begins single-user operation  by  giving  the  superuser  a
       shell on the console.

       You  can  use  the 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 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 which has been waiting 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 appropriate 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 used to be active in 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  sig-
       nal to the process, using kill -HUP 1.

       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 deadlocked (due to hardware or software failure), does not wait for  them
       all to die, but times out after 30 seconds and prints a warning message.

       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 will reboot itself automatically.  If, at bootstrap time, the process cannot be located, the system will loop  in  user
       mode at location 0x13.

Options
       -a   Specifies that the system should autoreboot to multiuser mode.  This option is similar to specifying to the console prompt or specify-
	    ing either with the -r option or from the command line.

       -s   Specifies that the system should boot to single-user mode.

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
       persistent 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 indi-
       cate 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
       Lists 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 Also
       ttys(5), getty(8), rc(8), reboot(8)

								       RISC								   init(8)