NAME

net_hook_register - add a hook to be called in event processing

SYNOPSIS

#include <sys/neti.h>
int net_hook_register(net_handle_t info, char *event, hook_t *hook);

INTERFACE LEVEL

illumos DDI specific (illumos DDI).

PARAMETERS

info

value returned from a successful call to net_protocol_register().

name

unique name for this hook.

hook

pointer to a hook_t structure.

DESCRIPTION

The net_hook_register() function uses hooks that allow callbacks to be registered with events that belong to a network protocol. A successful call to net_hook_register() requires that a valid handle for a network protocol be provided (the info parameter), along with a unique name and a hook description that includes a reference to an available event. No two hooks on the same netstack may share a name.

While it is possible to use the same hook_t structure with multiple calls to net_hook_register(), it is not encouraged.

The hook_t structure passed in with this function is described by hook_t(9S). The following describes how this structure is used.

h_func

Must be non-NULL and represent a function that fits the specified interface.

h_name

Gives the hook a name that represents its owner. No duplication of h_name among the hooks present for an event is allowed.

h_flags

Currently unused and must be set to 0.

h_hint, h_hintvalue

Specify a hint to net_hook_register() on how to insert this hook. If the hint cannot be specified, then an error is returned.

h_arg;

May take any value that the consumer wishes to have passed back when the hook is activated.

RETURN VALUES

If the net_hook_register() function succeeds, 0 is returned. Otherwise, one of the following errors is returned:

ENOMEM

The system cannot allocate any more memory to support registering this hook.

ENXIO

A hook cannot be found among the given family of events.

EEXIST

A hook with the given h_name already exists on that event.

ESRCH

A before or after dependency cannot be satisfied due to the hook with

EBUSY

The h_hint field specifies a hint that cannot currently be satisfied because it conflicts with another hook. An example of this might be specifying HH_FIRST or HH_LAST when another hook has already been registered with this value.

ESHUTDOWN

The netstack corresponding to info is condemned or no longer exists.

CONTEXT

The net_hook_register() function may be called from user or kernel context.

ATTRIBUTES

See attributes(7) for descriptions of the following attributes:

ATTRIBUTE TYPE	ATTRIBUTE VALUE
Interface Stability	Committed