runuser - run a command with substitute user and group ID


   runuser [options] -u user command [argument...]

   runuser [options] [-] [user [argument...]]


   runuser allows to run commands with a substitute user and group ID.  If
   the option -u is not given, it falls back  to  su-compatible  semantics
   and  a  shell is executed.  The difference between the commands runuser
   and su is that runuser does not ask for a password (because it  may  be
   executed   by  the  root  user  only)  and  it  uses  a  different  PAM
   configuration.  The command runuser does not have to be installed  with
   suid permissions.

   If  the PAM session is not required then recommended solution is to use
   setpriv(1) command.

   When  called  without  arguments,  runuser  defaults  to   running   an
   interactive shell as root.

   For  backward compatibility, runuser defaults to not change the current
   directory and to only set the  environment  variables  HOME  and  SHELL
   (plus  USER  and LOGNAME if the target user is not root).  This version
   of runuser uses PAM for session management.


   -c, --command=command
          Pass command to the shell with the -c option.

   -f, --fast
          Pass -f to the shell, which may or may not be  useful  depending
          on the shell.

   -g, --group=group
          The  primary  group  to be used.  This option is allowed for the
          root user only.

   -G, --supp-group=group
          Specify a supplemental group.  This option is available  to  the
          root user only.  The first specified supplementary group is also
          used as a primary group if the option --group is unspecified.

   -, -l, --login
          Start the shell as a login shell with an environment similar  to
          a real login:

             o      clears all the environment variables except for TERM

             o      initializes  the  environment  variables  HOME, SHELL,
                    USER, LOGNAME, PATH

             o      changes to the target user's home directory

             o      sets argv[0] of the shell to '-' in order to make  the
                    shell a login shell

   -m, -p, --preserve-environment
          Preserve  the  entire  environment,  i.e.  it does not set HOME,
          SHELL, USER nor LOGNAME.  The option is ignored  if  the  option
          --login is specified.

   -s, --shell=shell
          Run  the  specified  shell instead of the default.  The shell to
          run is selected according to the following rules, in order:

             o      the shell specified with --shell

             o      the shell specified in the environment variable  SHELL
                    if the --preserve-environment option is used

             o      the  shell  listed  in  the passwd entry of the target

             o      /bin/sh

          If the target user has a restricted shell (i.e.  not  listed  in
          /etc/shells)  the  --shell  option  and  the  SHELL  environment
          variables are ignored unless the calling user is root.

          Same as -c , but do not create a new session.  (Discouraged.)

   -V, --version
          Display version information and exit.

   -h, --help
          Display help text and exit.


   runuser   reads   the    /etc/default/runuser    and    /etc/login.defs
   configuration  files.   The  following configuration items are relevant
   for runuser:

   ENV_PATH (string)
       Defines the PATH environment variable  for  a  regular  user.   The
       default value is /usr/local/bin:/bin:/usr/bin.

   ENV_ROOTPATH (string)
   ENV_SUPATH (string)
       Defines  the  PATH environment variable for root. The default value
       is /usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin.

   ALWAYS_SET_PATH (boolean)
       If set to yes  and  --login  and  --preserve-environment  were  not
       specified runuser initializes PATH.


   runuser  normally  returns  the exit status of the command it executed.
   If the command was killed by a signal, runuser returns  the  number  of
   the signal plus 128.

   Exit status generated by runuser itself:

             1      Generic error before executing the requested command

             126    The requested command could not be executed

             127    The requested command was not found


                    default PAM configuration file
                    PAM configuration file if --login is specified
                    runuser specific logindef config file
   /etc/login.defs  global logindef config file


   pam(8), shells(5), login.defs(5), su(1), setpriv(1)


   This   runuser  command was derived from coreutils' su, which was based
   on an implementation by David MacKenzie, and the Fedora runuser command
   by Dan Walsh.


   The  runuser command is part of the util-linux package and is available
   from Linux Kernel  Archive


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