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CPU_REBOOT(9) NetBSD Kernel Developer's Manual CPU_REBOOT(9)
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by Kimmo Suominen.
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cpu_reboot -- halt or reboot the system
cpu_reboot(int howto, char *bootstr);
The cpu_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 auto-
If the system has finished autoconfiguration, cpu_reboot() does the fol-
1. Sets the boothowto system variable (see boothowto(9)) from the
2. If this is the first invocation of cpu_reboot() and the
RB_NOSYNC flag is not set in howto, syncs and unmounts the
system disks by calling vfs_shutdown(9) and sets the time of
day clock by calling resettodr(9).
3. Disables interrupts.
4. If rebooting after a crash (i.e., if RB_DUMP is set in howto,
but RB_HALT is not), saves a system crash dump.
5. Runs any shutdown hooks by calling pmf_system_shutdown(9).
6. Prints a message indicating that the system is about to be
halted or rebooted.
7. If RB_HALT is set in howto, halts the system. Otherwise,
reboots the system.
If the system has not finished autoconfiguration, cpu_reboot() runs any
shutdown hooks by calling pmf_system_shutdown(9), prints a message, and
halts the system.
If RB_STRING is set in howto, then the parameter bootstr is passed to the
system boot loader on some ports.
boothowto(9), dumpsys(9), pmf_system_shutdown(9), resettodr(9),
NetBSD 6.0 February 11, 2010 NetBSD 6.0