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inittab(4)                       File Formats                       inittab(4)



NAME
       inittab - script for init

DESCRIPTION
       The  /etc/inittab  file  controls process dispatching by init. The pro-
       cesses most typically dispatched by init are daemons.

       It is no longer necessary  to  edit  the  /etc/inittab  file  directly.
       Administrators should use the Solaris Service Management Facility (SMF)
       to define services instead. Refer to smf(5) and the System  Administra-
       tion Guide: Basic Administration for more information on SMF.

       To modify parameters passed to ttymon(1M), use svccfg(1M) to modify the
       SMF repository. See ttymon(1M) for details on the available SMF proper-
       ties.

       The inittab file is composed of entries that are position dependent and
       have the following format:

              id:rstate:action:process


       Each entry is delimited by a newline; however, a backslash (\)  preced-
       ing  a newline indicates a continuation of the entry. Up to 512 charac-
       ters for each entry are permitted. Comments  may  be  inserted  in  the
       process  field  using  the  convention for comments described in sh(1).
       There are no limits (other than maximum entry size) imposed on the num-
       ber of entries in the inittab file. The entry fields are:

       id

           One  to  four characters used to uniquely identify an entry. Do not
           use the characters "r" or "t" as the first  or  only  character  in
           this  field. These characters are reserved for the use of rlogin(1)
           and telnet(1).



       rstate

           Define the run level in which this entry is to be  processed.  Run-
           levels  effectively  correspond  to a configuration of processes in
           the system. That is, each process spawned by init is assigned a run
           level(s) in which it is allowed to exist. The run levels are repre-
           sented by a number ranging from 0 through 6. For  example,  if  the
           system  is  in  run  level  1, only those entries having a 1 in the
           rstate field are processed.

           When init is requested to change run levels, all processes that  do
           not  have an entry in the rstate field for the target run level are
           sent the warning signal SIGTERM and allowed a 5-second grace period
           before  being  forcibly terminated by the kill signal SIGKILL.  The
           rstate field can define  multiple  run  levels  for  a  process  by
           selecting more than one run level in any combination from 0 through
           6. If no run level is specified, then the process is assumed to  be
           valid at all run levels 0 through 6.

           There  are  three other values, a, b and c, which can appear in the
           rstate field, even though they are not  true  run  levels.  Entries
           which  have these characters in the rstate field are processed only
           when an init or telinit process requests them to be run (regardless
           of the current run level of the system). See init(1M). These differ
           from run levels in that init can never enter run level a, b  or  c.
           Also,  a  request  for the execution of any of these processes does
           not change the current run level. Furthermore, a process started by
           an  a,  b or c command is not killed when init changes levels. They
           are killed only if their line in  inittab  is  marked  off  in  the
           action  field, their line is deleted entirely from inittab, or init
           goes into single-user state.



       action

           Key words in this field tell init how to treat the  process  speci-
           fied  in  the  process field. The actions recognized by init are as
           follows:


           respawn

               If the process does not exist, then start the process;  do  not
               wait  for its termination (continue scanning the inittab file),
               and when the process dies, restart the process. If the  process
               currently  exists, do nothing and continue scanning the inittab
               file.




           wait

               When init enters the run level that matches the entry's rstate,
               start  the process and wait for its termination. All subsequent
               reads of the inittab file while init is in the same  run  level
               cause init to ignore this entry.



           once

               When  init  enters a run level that matches the entry's rstate,
               start the process, do not wait for  its  termination.  When  it
               dies,  do  not  restart  the  process. If init enters a new run
               level and the process is still  running  from  a  previous  run
               level change, the program is not restarted.



           boot

               The  entry  is to be processed only at init's boot-time read of
               the inittab file. init is to start the process and not wait for
               its termination; when it dies, it does not restart the process.
               In order for this instruction  to  be  meaningful,  the  rstate
               should be the default or it must match init's run level at boot
               time. This action is useful for an initialization function fol-
               lowing a hardware reboot of the system.



           bootwait

               The entry is to be processed the first time init goes from sin-
               gle-user to multi-user state after the system is  booted.  init
               starts  the  process,  waits  for  its termination and, when it
               dies, does not restart the process.



           powerfail

               Execute the process associated with this entry only  when  init
               receives a power fail signal, SIGPWR (see signal(3C)).



           powerwait

               Execute  the  process associated with this entry only when init
               receives a power fail signal, SIGPWR, and wait until it  termi-
               nates before continuing any processing of inittab.



           off

               If the process associated with this entry is currently running,
               send the warning signal  SIGTERM  and  wait  5  seconds  before
               forcibly  terminating the process with the kill signal SIGKILL.
               If the process is nonexistent, ignore the entry.



           ondemand

               This instruction is really a synonym for  the  respawn  action.
               It  is functionally identical to respawn but is given a differ-
               ent keyword in order to divorce its association with  run  lev-
               els.  This  instruction  is used only with the a, b or c values
               described in the rstate field.



           sysinit

               Entries of this type are executed before init tries  to  access
               the  console (that is, before the Console Login: prompt). It is
               expected that this  entry  will  be  used  only  to  initialize
               devices  that  init  might  try  to ask the run level question.
               These entries are executed and init waits for their  completion
               before continuing.



       process

           Specify  a command to be executed. The entire process field is pre-
           fixed with exec and passed to a forked sh as sh -c 'exec  command'.
           For  this  reason,  any  legal  sh syntax can appear in the process
           field.



SEE ALSO
       sh(1),  who(1),  init(1M),  svcadm(1M),   svc.startd(1M),   ttymon(1M),
       exec(2), open(2), signal(3C), smf(5)

       System Administration Guide: Basic Administration

NOTES
       With  the  introduction of the service management facility, the system-
       provided /etc/inittab file is greatly reduced from previous releases.

       The initdefault entry is not recognized in Solaris 10. See  smf(5)  for
       information  on  SMF  milestones,  and  svcadm(1M), which describes the
       "svcadm milestone -d" command; this provides similar  functionality  to
       modifying the initdefault entry in previous versions of the Solaris OS.



SunOS 5.10                        9 Dec 2004                        inittab(4)