doshutdownhooks(9) [netbsd man page]

DOSHUTDOWNHOOKS(9)					   BSD Kernel Developer's Manual					DOSHUTDOWNHOOKS(9)

NAME

     doshutdownhooks -- run all shutdown hooks

SYNOPSIS

     void
     doshutdownhooks(void);

DESCRIPTION

     The doshutdownhooks routine is deprecated. Use pmf_system_shutdown(9) instead.

     The doshutdownhooks() function invokes all shutdown hooks established using the shutdownhook_establish(9) function.  Shutdown hooks are
     called in reverse order, i.e., the shutdown hook established last will be called first.

     This function is called from cpu_reboot() with interrupts turned off.  It is called immediately before the system is halted or rebooted,
     after file systems have been unmounted, after the clock has been updated, and after a system dump has been done (if necessary).

SEE ALSO

     cpu_reboot(9), shutdownhook_establish(9)

BSD
								 February 11, 2010							       BSD

SHUTDOWNHOOK_ESTABLISH(9)				   BSD Kernel Developer's Manual				 SHUTDOWNHOOK_ESTABLISH(9)

NAME

     shutdownhook_establish, shutdownhook_disestablish -- add or remove a shutdown hook

SYNOPSIS

     void *
     shutdownhook_establish(void (*fn)(void *), void *arg);

     void
     shutdownhook_disestablish(void *cookie);

DESCRIPTION

     The shutdownhook_establish API is deprecated.

     The shutdownhook_establish() function adds fn to the list of hooks invoked by doshutdownhooks(9) at shutdown.  When invoked, the hook func-
     tion fn will be passed arg as its only argument.

     The shutdownhook_disestablish() function removes the hook described by the opaque pointer cookie from the list of hooks to be invoked at
     shutdown.	If cookie is invalid, the result of shutdownhook_disestablish() is undefined.

     Shutdown hooks should be used to perform one-time activities that must happen immediately before the kernel exits.  Because of the environ-
     ment in which they are run, shutdown hooks cannot rely on many system services (including file systems, and timeouts and other interrupt-
     driven services), or even basic system integrity (because the system could be rebooting after a crash).

RETURN VALUES

     If successful, shutdownhook_establish() returns an opaque pointer describing the newly-established shutdown hook.	Otherwise, it returns
     NULL.

EXAMPLES

     It may be appropriate to use a shutdown hook to disable a device that does direct memory access, so that the device will not try to access
     memory while the system is rebooting.

     It may be appropriate to use a shutdown hook to inform watchdog timer hardware that the operating system is no longer running.

SEE ALSO

     doshutdownhooks(9)

BUGS

     The names are clumsy, at best.

BSD
								   May 14, 2009 							       BSD