T_CONN_REQ(D7tpi)

T_CONN_REQ -- Connect Request

Synopsis

This message consists of one M_PROTO message block followed by zero or more M_DATA blocks if any user data is specified by the transport user. The format of the M_PROTO message block is as follows:

   struct T_conn_req {
   	long 	PRIM_type; 	/* always T_CONN_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 connect 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.

Note that the information located by the defined structures may not be in the proper alignment in the message blocks, so the casting of structure definitions over these fields may produce incorrect results. It is advised that the transport providers supply exact format specifications for the appropriate information to the transport users.

The destination address and options in the M_PROTO message block are however, aligned the same as they were received from the transport user.

Rules

This primitive requires the transport provider to generate one of the following acknowledgments on receipt of the primitive, and the transport user must wait for the acknowledgment before issuing any other primitives:

Successful: Correct acknowledgment of the primitive is indicated via the T_OK_ACK primitive described in
Non-fatal errors: These errors will be indicated via the T_ERROR_ACK primitive described in

Errors

The allowable errors are as follows:

TACCES: This indicates that the user did not have proper permissions for the use of the requested address or options.
TBADADDR: This indicates that the protocol address was in an incorrect format or the address contained invalid information. It is not intended to indicate protocol connection errors, such as an unreachable destination. Those error types are indicated via the T_DISCON_IND primitive.
TBADOPT: This indicates that the options were in an incorrect format, or they contained invalid information.
TOUTSTATE: The primitive would place the transport interface out of state.
TBADDATA: The amount of user data specified was invalid.
TSYSERR: A system error has occurred and the UNIX system error is indicated in the primitive.
TNOTSUPPORT: This primitive is not supported by the transport provider.
TADDRBUSY: The transport provider does not support multiple connections to the same destination address. This error indicates that a connection already exists for the requested destination.

Modes

Only connection-mode.

Originator

Transport user.

Notices

Hardware constraints

None

Applicability

N/A

Backward compatibility

UnixWare-specific TPI Message Formats

Forward compatibility

N/A