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      NAME
           inittab - script for the startup process

      DESCRIPTION
           The inittab file supplies the script to startup's role as a
           general process dispatcher. The process that constitutes the
           majority of startup's process dispatching activities is the
           line process /etc/getty that initiates individual terminal
           lines.  Other processes typically dispatched by startup are
           daemons and the shell.

           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 per entry are permitted.
           Comments may be inserted in the process field using the
           sh(1) convention for comments.  Comments for lines that
           spawn gettys are displayed by the who(1) command.  It is
           expected that they will contain some information about the
           line such as the location.  There are no limits (other than
           maximum entry size) imposed on the number of entries within
           the inittab file.  The entry fields are:

           id        This is one to four characters used to uniquely
                     identify an entry.

           rstate    This defines 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 startup is
                     assigned a run-level or run-levels in which it is
                     allowed to exist.  The run-levels are represented
                     by a number ranging from 0 through 6.  As an
                     example, if the system is in run-level 1, only
                     those entries having a 1 in the rstate field will
                     be processed. The rstate field can define multiple
                     run-levels for a process by selecting more than
                     one run-level in any combination from 0-6.  If no
                     run-level is specified, then the process is
                     assumed to be valid at all run-levels 0-6.

           action    Key words in this field tell startup how to treat
                     the process specified in the process field.  The
                     actions recognized by startup are as follows:

                     respawn       If the process does not exist then
                                   start the process, do not wait for
                                   its termination (continue scanning



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                                   the inittab file), and when it dies
                                   restart the process.  If the process
                                   currently exists then do nothing and
                                   continue scanning the inittab file.

                     wait          Upon startup's entering the run-
                                   level that matches the entry's
                                   rstate, start the process and wait
                                   for its termination.

                     once          Upon startup's entering 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.

                     boot          The entry is to be processed only at
                                   startup's boot-time read of the
                                   inittab file. Startup is to start
                                   the process, not wait for its
                                   termination; and when it dies, not
                                   restart the process.  In order for
                                   this instruction to be meaningful,
                                   the rstate should be the default or
                                   it must match startup'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 only at
                                   startup's boot-time read of the
                                   inittab file.  Startup is to start
                                   the process, wait for its
                                   termination and, when it dies, not
                                   restart the process.

                     off           Ignore the entry.

                     initdefault   An entry with this action is only
                                   scanned when startup is initially
                                   invoked.  Startup uses this entry,
                                   if it exists, to determine which
                                   run-level to enter initially.  It
                                   does this by taking the highest
                                   run-level specified in the rstate
                                   field and using that as its initial
                                   state. If the rstate field is empty,
                                   this is interpreted as 0123456 and
                                   so startup will enter run-level 6.
                                   Also, the initdefault entry cannot
                                   specify that startup start in the



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                                   SINGLE USER state.  Additionally, if
                                   startup does not find an initdefault
                                   entry in /etc/inittab, then it will
                                   request an initial run-level from
                                   the user at reboot time.

                     sysinit       Entries of this type are executed
                                   before startup tries to access the
                                   console.  It is expected that this
                                   entry will be only used to
                                   initialize devices on which startup
                                   might try to ask the run-level
                                   question.  These entries are
                                   executed and waited for before
                                   continuing.

           process   This is a sh command to be executed.  The entire
                     process field is prefixed 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.  Comments can be inserted with the
                     #or ; :comment syntax.

      FILES
           /etc/inittab

      SEE ALSO
           getty(1), sh(1), who(1)



























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