ZCOM Tables and Data Structures

ZCOM Header Structure

HLTSTB - Storage label table

The storage label entry indicates the ownership of an application data storage area in the logical terminal table extension area. Each entry is a structure of 16 bytes (zslb_type), as shown in Table 3-3.

Table 3-3

Storage Label Table

 

 

 

 

 

 

Field Name

Field Description

Field Type

Size

(Bytes)

 

 

 

 

 

 

 

SLBGRP

Appl. grp. number (0 = globally assigned)

uns.short

2

 

 

 

 

SLBNAM

Storage label name

char

8

 

 

 

 

SLBSZE

Size of the application data in bytes

uns.short

2

 

 

 

 

SLBOFF

Offset from the start of the LTT to the

short

2

 

application data in the extension area.

 

 

 

Therefore, this value is the size of the LTT plus

 

 

 

the offset of the application data from the start

 

 

 

of the LTT extension area.

 

 

 

 

 

 

SLBRSV

<reserved>, unused

char

2

 

 

 

 

The table is initialized by TTGEN from the Logical-Datastatements in the TTGEN configuration file. There is one entry in the Storage label table for each Logical-Datastatement. Additional entries can be added to this table by calling the zltqueue() routine (up to a maximum of 20 storage labels).

DSC_ercvrs - Dynamic Reconfiguration System Event Receivers pointer (zshaddr_type *)

This field contains a pointer to a linked list of all applications that wish to be notified whenever a ZCOM subsystem dynamic reconfiguration system event message is generated (through the zconfig routine). This field is initialized by TTGEN to zero. It will only contain a value if at least one application has requested notification.

ETPLIM- Default E1/T1 IFT port TX limit (bytes)

This field contains the limit (in bytes) of all unacknowledged transmit messages to terminal ZLUs belonging to the same port and subchannel of an E1/T1 card. Each E1/T1 card has approximately 16 M-bytes of buffer space available for both internal use and transmit requests. If the DAM

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