KERN_REBOOT(9)         FreeBSD Kernel Developer's Manual        KERN_REBOOT(9)

NAME
     kern_reboot - halt or reboot the system

SYNOPSIS
     #include <sys/types.h>
     #include <sys/systm.h>
     #include <sys/reboot.h>

     void
     kern_reboot(int howto);

     #include <sys/eventhandler.h>

     EVENTHANDLER_REGISTER(shutdown_pre_sync, shutdown_fn, private, priority);

     EVENTHANDLER_REGISTER(shutdown_post_sync, shutdown_fn, private,
         priority);

     EVENTHANDLER_REGISTER(shutdown_final, shutdown_fn, private, priority);

DESCRIPTION
     The kern_reboot() function handles final system shutdown, and either
     halts or reboots the system.  The exact action to be taken is determined
     by the flags passed in howto and by whether or not the system has
     finished autoconfiguration.

     If the system has finished autoconfiguration, kern_reboot() does the
     following:

           1.   If this is the first invocation of kern_reboot() and the
                RB_NOSYNC flag is not set in howto, syncs and unmounts the
                system disks by calling vfs_unmountall(9).

           2.   Disables interrupts.

           3.   If rebooting after a crash (i.e., if RB_DUMP is set in howto,
                but RB_HALT is not), saves a system crash dump.

           4.   Runs any shutdown hooks previously registered.

           5.   Prints a message indicating that the system is about to be
                halted or rebooted.

           6.   If RB_HALT is set in howto, halts the system.  Otherwise,
                reboots the system.

     If the system has not finished autoconfiguration, kern_reboot() runs any
     shutdown hooks previously registered, prints a message, and halts the
     system.

RETURN VALUES
     The kern_reboot() function does not return.

SEE ALSO
     reboot(2) EVENTHANDLER(9) vfs_unmountall(9)

FreeBSD 13.1-RELEASE-p6          Sept 23, 2021         FreeBSD 13.1-RELEASE-p6