T_DATA_IND(D7tpi)

T_DATA_IND -- Data Indication

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 at least one byte of data. The format of the M_PROTO message block is as follows:

   struct T_data_ind {
   	long PRIM_type;	 /* always T_DATA_IND */
   	long MORE_flag;	 /* indicates more data in TSDU */
   }

Description

This primitive indicates to the transport user that this message contains a transport interface data unit. One or more transport interface data units form a transport service data unit. This primitive has a mechanism which indicates the beginning and end of a transport service data unit. However, not all transport providers support the concept of a transport service data unit.

Parameters

PRIM_type: identifies the primitive type.
MORE_flag: when greater than zero, indicates that the next T_DATA_IND primitive is also part of this transport service data unit.

Rules

If a TSDU spans multiple T_DATA_IND message blocks, then an ETSDU may be placed in between two T_DATA_IND message blocks. Once an ESTDU is started, then the ETSDU must be completed before any T_DATA_IND message blocks defining a TSDU is resumed.

Modes

Only connection-mode.

Originator

Transport provider.

Notices

Hardware constraints

None

Applicability

N/A

Backward compatibility

UnixWare-specific TPI Message Formats

Forward compatibility

N/A