Tribblix: manual page: dlpi

DLPI_ENABNOTIFY(3DLPI) Data Link Provider Interface Library Functions

NAME

dlpi_enabnotify - enable DLPI notification

SYNOPSIS

cc [ flag... ] file... -ldlpi [ library... ]
#include <libdlpi.h>

int dlpi_enabnotify(dlpi_handle_t dh, uint_t notes,
dlpi_notifyfunc_t *funcp, void *arg, dlpi_notifyid_t *id);

typedef void dlpi_notifyfunc_t(dlpi_handle_t,
dlpi_notifyinfo_t *, void *);

DESCRIPTION

The dlpi_enabnotify() function enables a notification callback for
the set of events specified in notes, which must be one or more (by a
logical OR operation) of the DLPI notifications documented in
dlpi(4P). The callback function funcp is registered with the DLPI
handle dh and is invoked when dh receives notification for any of the
specified event types. Upon success, id contains the identifier
associated with the registration.

Multiple event types can be registered for a callback function on the
DLPI handle dh. Similarly, the same event type can be registered
multiple times on the same handle.

Once a callback has been registered, libdlpi will check for
notification events on the DLPI handle dh, when exchanging DLPI
messages with the underlying DLPI link instance. The dlpi_recv(3DLPI)
function will always check for notification events, but other libdlpi
operations may also lead to an event callback being invoked. Although
there may be no expected data messages to be received, dlpi_recv()
can be called, as shown below, with a null buffer to force a check
for pending events on the underlying DLPI link instance.

dlpi_recv(dh, NULL, NULL, NULL, NULL, 0, NULL);

When a notification event of interest occurs, the callback function
is invoked with the arguments arg, originally passed to
dlpi_disabnotify(3DLPI), and infop, whose members are described
below.

uint_t dni_note
Notification event type.

uint_t dni_speed
Current speed, in kilobits per second, of
the DLPI link. Valid only for
DL_NOTE_SPEED.

uint_t dni_size
Current maximum message size, in bytes,
that the DLPI link is able to accept for
transmission. Valid only for
DL_NOTE_SDU_SIZE.

uchar_t dni_physaddrlen
Link-layer physical address length, in
bytes. Valid only for DL_NOTE_PHYS_ADDR.

uchar_t dni_physaddr[]
Link-layer physical address of DLPI link.
Valid only for DL_NOTE_PHYS_ADDR.

The libdlpi library will allocate and free the dlpi_notifyinfo_t
structure and the caller must not allocate the structure or perform
any operations that require its size to be known.

The callback is not allowed to block. This precludes calling
dlpi_enabnotify() from a callback, but non-blocking libdlpi
functions, including dlpi_disabnotify(), can be called.

RETURN VALUES

Upon success, DLPI_SUCCESS is returned. If DL_SYSERR is returned,
errno contains the specific UNIX system error value. Otherwise, a
DLPI error value defined in <sys/dlpi.h> or an error value listed in
the following section is returned.

ERRORS

DLPI_EINHANDLE
A DLPI handle is invalid.

DLPI_EINVAL
An argument is invalid.

DLPI_ENOTEIDINVAL
The DLPI notification ID is invalid.

DLPI_ENOTENOTSUP
The DLPI notification is not supported by the
link.

DLPI_ETIMEDOUT
The DLPI operation timed out.

DLPI_FAILURE
The DLPI operation failed.