NAME

SYNOPSIS

int
g_post_event(g_event_t *func, void *arg, int flag, ...);

int
g_waitfor_event(g_event_t *func, void *arg, int flag, ...);

void
g_cancel_event(void *ref);

struct g_event *
g_alloc_event(int flag);

void
g_post_event_ep(g_event_t *func, void *arg, struct g_event *ep, ...);

DESCRIPTION

The g_post_event() function tells the GEOM framework to call function func with argument arg from the event queue. The flag argument is passed to malloc(9) for memory allocations inside of g_post_event(). The only allowed flags are M_WAITOK and M_NOWAIT. The rest of the arguments are used as references to identify the event. An event can be canceled by using any of the given references as an argument to g_cancel_event(). The list of references has to end with a NULL value.

The g_waitfor_event() function is a blocking version of the g_post_event() function. It waits until the event is finished or canceled and then returns.

The g_post_event_ep() function posts the event with a pre-allocated struct g_event. An event may be pre-allocated with g_alloc_event().

The g_cancel_event() function cancels all event(s) identified by ref. Cancellation is equivalent to calling the requested function with requested arguments and argument flag set to EV_CANCEL.

RESTRICTIONS/CONDITIONS

• The argument flag has to be M_WAITOK or M_NOWAIT.
• The list of references has to end with a NULL value.

g_waitfor_event():

• The argument flag has to be M_WAITOK or M_NOWAIT.
• The list of references has to end with a NULL value.
• The g_waitfor_event() function cannot be called from an event, since doing so would result in a deadlock.

g_alloc_event():

• The argument flag has to be M_WAITOK or M_NOWAIT.
• The returned struct g_event * must be freed with g_free() if g_post_event_ep() is not called.

RETURN VALUES

EXAMPLES

void
example_event(void *arg, int flag)
{

	if (flag == EV_CANCEL) {
		printf("Event with argument %p canceled.\n", arg);
		return;
	}

	printf("Event with argument %p called.\n", arg);
}

ERRORS

[ENOMEM]

The flag argument was set to M_NOWAIT and there was insufficient memory.

Possible errors for the g_waitfor_event() function:

[EAGAIN]

The event was canceled.

[ENOMEM]

The flag argument was set to M_NOWAIT and there was insufficient memory.

SEE ALSO

AUTHORS