ZCOM Tables and Data Structures

Logical Terminal Tables

LTAPNO - System application number

This field is initialized by TTGEN based on the value specified in the Term or Lterm statement in the TTGEN configuration file. This field is not used by the ZCOM subsystem. It allows applications to recognize the terminals which are assigned to it. Each ZCOM application which is a direct receiver of terminal messages should access only those terminals with its allocated application number.

LTINST, LTBRCH, LTWORK, LTAREA - Terminal logical ID

These logical terminal ID fields describe the owner and location of the terminal at an application program level. At this level the physical parameters are not relevant. Because these fields are at an application level, their contents are largely dependent on the particular application.

LTNAME - Terminal name

This is a 30-byte ASCII description of the terminal. It is used by the ZCOM utility programs as well as application programs. The field is initialized from the desc parameter of the Term or Lterm statements in the TTGEN configuration file.

The logical terminal table extension follows the basic table, and is used exclusively by the application programs. The size of this area is specified in the HLTDSZE field in the ZCOM header table (zheader_type).

Chapter 3

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