init - systeme de gestion d'initialisation

init [-fs]

Le programme init est la derniere etape du processus de boot. Ça execute normallement la sequence des evenements decrite dans rc(8) et si cela reussis, les operation multi-utilisateur commencent. Si le script de boot echoue, init demarre les operations en simple-utilisateur pour donner au superutilisateur un shell sur la console. Le programme init peut être passé en paramètre à partir du programme de boot pour prévenir le fait que le systeme passe en multiutilisateur et pour, à la place, éxecuter un invité de commande simple utilisateur sans initialiser les démons normaux.

Les paramètres suivant peuvent être passé depuis le programme de démarrage :

-f Active le mode démarrage-éclair

-s Démarre directement dans le mode utilisateur simple.

  The system is then quiescent for maintenance work and may later be made
   to go to multi-user by exiting the single-user shell (with ^D).  This
   causes init to run the /etc/rc startup command file in fastboot mode
   (skipping disk checks).

   If the console entry in the [[:maxime:openbsd:manpages-fr:5:ttys|ttys(5)]] file does not contain the ``secure''
   flag, then init will require that the superuser password be entered be-
   fore the system will start a single-user shell.  The password check is
   skipped if the console is marked as ``secure''.

   The kernel [[:maxime:openbsd:manpages-fr:7:securelvel|securelevel(7)]] is normally set to 0 while in single-user mode,
   and raised to 1 when the system begins multi-user operations.  This ac-
   tion will not take place if the securelevel is -1, and can be modified
   via the /etc/rc.securelevel script.

   In multi-user operation, init maintains processes for the terminal ports
   found in the file [[:maxime:openbsd:manpages-fr:5:ttys|ttys(5)]].  init reads this file, and executes the com-
   mand found in the second field.  This command is usually [[:maxime:openbsd:manpages-fr:8:getty|getty(8)]]; getty
   opens and initializes the tty line and executes the login program.  The
   login program, when a valid user logs in, executes a shell for that user.
   When this shell dies, either because the user logged out or an abnormal
   termination occurred (a signal), the init program wakes up, deletes the
 user from the [[:maxime:openbsd:manpages-fr:5:utmp|utmp(5)]] file of current users and records the logout in the
   wtmp file.  The cycle is then restarted by init executing a new getty for
   the line.

   Line status (on, off, secure, getty, or window information) may be
   changed in the ttys file without a reboot by sending the signal SIGHUP to
   init with the command ``kill -s HUP 1''.  On receipt of this signal, init
   re-reads the ttys file.  When a line is turned off in ttys, init will
   send a SIGHUP signal to the controlling process for the session associat-
   ed with the line.  For any lines that were previously turned off in the
   ttys file and are now on, init executes a new getty to enable a new lo-
   gin.  If the getty or window field for a line is changed, the change
   takes effect at the end of the current login session (e.g., the next time
   init starts a process on the line).  If a line is commented out or delet-
   ed from ttys, init will not do anything at all to that line.  However, it
   will complain that the relationship between lines in the ttys file and
   records in the utmp file is out of sync, so this practice is not recom-
   mended.

  init will terminate multi-user operations and resume single-user mode if
   sent a terminate (TERM) signal, for example, ``kill -s TERM 1''.  If
   there are processes outstanding that are deadlocked (because of hardware
   or software failure), init will not wait for them all to die (which might
   take forever), but will time out after 30 seconds and print a warning
   message.

   init will cease creating new [[:maxime:openbsd:manpages-fr:8:getty|getty(8)]] and allow the system to slowly die
   away, if it is sent a terminal stop (TSTP) signal, i.e., ``kill -s TSTP
   1''.  A later hangup will resume full multi-user operations, or a termi-
   nate will start a single-user shell.  This hook is used by [[:maxime:openbsd:manpages-fr:8:reboot|reboot(8)]] and
   [[:maxime:openbsd:manpages-fr:8:halt|halt(8)]].

   init will terminate multi-user operations, kill all [[:maxime:openbsd:manpages-fr:8:getty|getty(8)]], run
   /etc/rc.shutdown, and halt the machine if user-defined signal 1 (USR1) or
   user-defined signal 2 is received.  /etc/rc.shutdown can specify that a
   powerdown is requested.  Alternatively, USR2 specifically requests a pow-
   erdown.

   The role of init is so critical that if it dies, the system will reboot
   itself automatically.  If, at bootstrap time, the init process cannot be
   located, the system will panic with the message ``panic: init died
   (signal %d, exit %d)''.

   When init spawns a process it sets the process priority, umask, and re-
   source limits based on /etc/login.conf.  When starting the [[:maxime:openbsd:manpages-fr:8:rc|rc(8)]] files,
   the login class ``daemon'' is used.  When starting a window system or
   [[:maxime:openbsd:manpages-fr:8:getty|getty(8)]], the login class ``default'' is used.  No resource changes are
   made when entering single user mode.

   /dev/console         system console device
   /dev/tty*            terminal ports found in ttys
   /etc/rc              system startup commands
   /etc/rc.securelevel  commands that run before the security level changes
   /etc/rc.shutdown     script run at shutdown time
   /etc/ttys            terminal initialization information file
   /fastboot            tells [[:maxime:openbsd:manpages-fr:8:rc|rc(8)]] not to run [[:maxime:openbsd:manpages-fr:8:fsck|fsck(8)]] during the next boot
   /var/run/utmp        record of users currently logged in
   /var/log/wtmp        record of all logins and logouts

   getty repeating too quickly on port %s, sleeping  A process being started
   to service a line is exiting quickly each time it is started.  This is
   often caused by a ringing or noisy terminal line.  Init will sleep for 10
   seconds, then continue trying to start the process.

   some processes would not die; ps axl advised.  A process is hung and
   could not be killed when the system was shutting down.  This condition is
   usually caused by a process that is stuck in a device driver because of a
   persistent device error condition.

kill(1), login(1), sh(1), fbtab(5), login.conf(5), ttys(5), securelevel(7), crash(8), getty(8), halt(8), rc(8), rc.shutdown(8), reboot(8), shutdown(8)

   Une commande init est apparue dans la version 6 de l'UNIX d'AT&T.

OpenBSD 4.4 24 août 2008 2