T_UNITDATA_REQ(7tpi) T_UNITDATA_REQ(7tpi)
NAME
T_UNITDATA_REQ - Unitdata Request
SYNOPSIS
This message consists of one M_PROTO message block followed by
zero or more M_DATA message blocks where each M_DATA message
block contains zero or more bytes of data. The format of the
M_PROTO message block is as follows:
struct T_unitdata_req {
long PRIM_type; /* always T_UNITDATA_REQ */
long DEST_length; /* dest addr length */
long DEST_offset; /* dest addr offset */
long OPT_length; /* options length */
long OPT_offset; /* options offset */
}
DESCRIPTION
This primitive requests that the transport provider send the
specified datagram to the specified destination.
Parameters
PRIM_type
identifies the primitive type.
DEST_length
is the length of the destination address
DEST_offset
is the offset (from the beginning of the M_PROTO message
block) where the destination address begins.
OPT_length
is the length of the requested options associated with
the primitive.
OPT_offset
is the offset (from the beginning of the M_PROTO message
block) of the requested options associated with the
primitive.
The proper alignment of the destination address and options in
the M_PROTO message block is not guaranteed. The destination
address and options in the M_PROTO message block are, however,
aligned the same as they were received from the transport
user.
Copyright 1994 Novell, Inc. Page 1
T_UNITDATA_REQ(7tpi) T_UNITDATA_REQ(7tpi)
This primitive does not require any acknowledgment. If a
non-fatal error occurs, it is the responsibility of the
transport provider to report it via the T_UDERROR_IND
indication. Fatal errors are indicated via a M_ERROR message
type which results in the failure of all operating system
service routines on the stream.
Errors
The allowable fatal errors are as follows:
EPROTO
This indicates one of the following unrecoverable
protocol conditions:
The transport service interface was found to be in
an incorrect state.
The amount of transport user data associated with
the primitive defines an transport service data
unit larger than that allowed by the transport
provider.
Modes
Only connectionless-mode.
Originator
Transport user.
Copyright 1994 Novell, Inc. Page 2