runlevel(8)                                                                                                          runlevel(8)



NAME
       runlevel - output previous and current runlevel

SYNOPSIS
       runlevel [OPTION]...  [UTMP]

DESCRIPTION
       runlevel  reads  the system UTMP file, which defaults to /var/run/utmp when no alternate filename is given, to locate the
       most recent runlevel record.

       The previous and current runlevel from that record are output separated by a single space.  If there is no previous  run-
       level in the record, the letter N will be substituted.

       If no runlevel record can be found, runlevel outputs the word unknown and exits with an error.

       During  system  boot, the environment variables RUNLEVEL and PREVLEVEL will be set by the init(8) daemon, these come from
       the runlevel(7) event generated by telinit(8) or shutdown(8).

       When these environment variables are set, runlevel will output the values from these instead.  Thus runlevel can be  used
       in rc scripts as a replacement for the System-V who(1) -r command.

OPTIONS
       --quiet
              Does  not  output  the current and previous runlevel, nor does it output unknown in the case of error (but it will
              exit with an error code).

              This may be used to test for the presence of a runlevel entry, or to check for errors reading from the file.

EXIT STATUS
       runlevel will exit with status 0 if a UTMP record was found, otherwise it will exit with status 1.

ENVIRONMENT
       RUNLEVEL
              runlevel will read the current runlevel from this environment variable  if  set  in  preference  to  reading  from
              /var/run/utmp

       PREVLEVEL
              runlevel will read the previous runlevel from this environment variable if RUNLEVEL
               was given, in preference to reading from /var/run/utmp

FILES
       /var/run/utmp
              Where the current and previous runlevels will be read from.

NOTES
       The  Upstart  init(8)  daemon  does  not  keep  track  of  runlevels itself, instead they are implemented entirely by its
       userspace tools.

       A change of runlevel is signalled by the runlevel(7) event, generated by either  the  telinit(8)  or  shutdown(8)  tools.
       This  event  includes  the  new runlevel in the RUNLEVEL environment variable, as well as the previous runlevel (obtained
       from their own environment or from /var/run/utmp) in the PREVLEVEL variable.

       As well as generating the event, both tools write the new runlevel back to  /var/run/utmp  and  append  a  new  entry  to
       /var/log/wtmp.

AUTHOR
       Written by Scott James Remnant <scottATnetsplit.com>

REPORTING BUGS
       Report bugs at <https://launchpad.net/upstart/+bugs>

COPYRIGHT
       Copyright (C) 2009 Canonical Ltd.
       This is free software; see the source for copying conditions.  There is NO warranty; not even for MERCHANTABILITY or FIT-
       NESS FOR A PARTICULAR PURPOSE.

SEE ALSO
       runlevel(7) init(8) telinit(8) shutdown(8) who(1)



Upstart                                                    2009-07-09                                                runlevel(8)