REBOOT(2V)              GENIX Programmer's Manual              REBOOT(2V)



      NAME
           reboot - reboot system or halt processor

      SYNOPSIS
           #include <sys/reboot.h>

           reboot(howto)
           int howto;

      DESCRIPTION
           Reboot is used to cause a system reboot, and  is  invoked  automati-
           cally  in  the  event  of unrecoverable system failures.  Howto is a
           mask of options passed to the bootstrap program.   The  system  call
           interface  permits  only  RB_HALT or RB_AUTOBOOT to be passed to the
           reboot program.  When none of these options  (e.g.  RB_AUTOBOOT)  is
           given,  the  system  is rebooted from file "vmunix" in the root file
           system of unit 0 of a disk chosen in a processor specific way: it is
           determined  by  the setting of the front switch pack switch 3 and 4.
           If both switch 3 and switch 4 are On then processor will  enter  the
           ROM monitor which will pick the bootstrap device.

           The bits of howto are:

           RB_HALT
                the processor is simply halted; no reboot takes place.  The Cpu
                locks out all interrupts and executes the WAIT instruction.

           RB_ASKNAME
                Interpreted by the bootstrap  program  itself,  causing  it  to
                inquire as to what file should be booted.  Normally, the system
                is booted from the file "xx(0,0)vmunix" without  asking,  where
                xx  is  determined  by a code in register r7 (which is known as
                devtype)  at  entry  to  the  bootstrap  program.    The   code
                corresponds to the major device number of the root file system,
                i.e. "major(rootdev)".   Currently,  the  following  values  of
                devtype are understood:

                     0    disk
                     1    tape

                Thus if r7 contained a 2, the system

                     dc(1,0)vmunix.

                would be booted.  This switch not  available  from  the  system
                call interface.

           RB_SINGLE
                Normally, the reboot procedure involves an automatic disk  con-
                sistency  check  and then multi-user operations.  This prevents
                the consistency check, rather simply booting the system with  a
                single-user   shell  on  the  console,  from  the  file  system



      Printed 11/16/83                                                        1

      REBOOT(2V)              GENIX Programmer's Manual              REBOOT(2V)



                specified by r7. This switch is interpreted by the init(8) pro-
                gram  in the newly booted system.  This switch is not available
                from the system call interface.

      SEE ALSO
           crash(8), halt(8), init(8), reboot(8)

















































      Printed 11/16/83                                                        2