NAME

       sulogin - single-user login

SYNOPSIS

       sulogin [options] [tty]

DESCRIPTION

       sulogin is invoked by init when the system goes into single-user mode.

       The user is prompted:

            Give root password for system maintenance
            (or type Control-D for normal startup):

       If the root account is locked and --force is specified, no password is required.

       sulogin will be connected to the current terminal, or to the optional tty device that can be specified on
       the command line (typically /dev/console).

       When the user exits from the single-user shell, or presses control-D  at  the  prompt,  the  system  will
       continue to boot.

OPTIONS

       -e, --force
              If  the  default method of obtaining the root password from the system via getpwnam(3) fails, then
              examine /etc/passwd and  /etc/shadow  to  get  the  password.   If  these  files  are  damaged  or
              nonexistent,  or  when  root  account  is  locked  by '!' or '*' at the begin of the password then
              sulogin will start a root shell without asking for a password.

              Only use the -e option if you are sure the console is physically  protected  against  unauthorized
              access.

       -p, --login-shell
              Specifying this option causes sulogin to start the shell process as a login shell.

       -t, --timeout seconds
              Specify the maximum amount of time to wait for user input.  By default, sulogin will wait forever.

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

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

ENVIRONMENT VARIABLES

       sulogin  looks  for the environment variable SUSHELL or sushell to determine what shell to start.  If the
       environment variable is not set, it will try to execute root's shell from /etc/passwd.  If that fails, it
       will fall back to /bin/sh.

AUTHOR

       sulogin was written by Miquel van Smoorenburg for sysvinit and later ported to util-linux by Dave Reisner
       and Karel Zak.

AVAILABILITY

       The sulogin command is part of the util-linux package and is available from Linux Kernel Archive  ⟨ftp://
       ftp.kernel.org/pub/linux/utils/util-linux/⟩.