man/man9f/net_hook_register.9f

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 NET_HOOK_REGISTER 9F "Mar 5, 2012"
 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

Solaris DDI specific (Solaris 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(5) for descriptions of the following attributes:


ATTRIBUTE TYPE ATTRIBUTE VALUE
Interface Stability Committed


 SEE ALSO

net_hook_unregister(9F), hook_t(9S)