Manual Pages for UNIX Operating System command usage for man inittab

File Formats                                           inittab(4)



NAME
     inittab - script for init

DESCRIPTION
     The /etc/inittab file controls process dispatching by  init.
     The processes 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  Administration  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 properties.


     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
     (\)  preceding  a  newline  indicates  a continuation of the
     entry. Up to 512 characters for each  entry  are  permitted.
     Comments may be inserted in the process field using the con-
     vention for comments described in sh(1). There are no limits
     (other  than  maximum  entry  size) imposed on the number 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  represented 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.




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File Formats                                           inittab(4)



                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 warn-
                ing  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  specified 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 pro-
                             cess 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  termi-
                             nation.  All subsequent reads of the
                             inittab file while init  is  in  the
                             same  run level cause init to ignore
                             this entry.




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File Formats                                           inittab(4)



                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 following  a
                             hardware reboot of the system.


                bootwait     The entry is  to  be  processed  the
                             first  time  init  goes from single-
                             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 terminates before continu-
                             ing 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



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File Formats                                           inittab(4)



                             SIGKILL.  If  the  process is nonex-
                             istent, ignore the entry.


                ondemand     This instruction is really a synonym
                             for  the respawn action. It is func-
                             tionally identical to respawn but is
                             given  a  different keyword in order
                             to divorce its association with  run
                             levels.  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 con-
                             sole (that is,  before  the  Console
                             Login:  prompt). It is expected that
                             this entry will be used only to ini-
                             tialize  devices that init might try
                             to ask the run level question. These
                             entries  are executed and init waits
                             for their completion before continu-
                             ing.



     process    Specify a command to be executed. The entire pro-
                cess  field is prefixed with exec and passed to a
                forked sh as sh -c 'exec command'. For this  rea-
                son,  any  legal sh syntax can appear in the pro-
                cess 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 pro-
     vides  similar  functionality  to  modifying the initdefault
     entry in previous versions of the Solaris OS.



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