ZCOM Tables and Data Structures

Node Entries Table

Node Entries Table

The Node Entries table contains information about the remote ZCOM systems that communicate with the local ZCOM subsystem. Each Local-Nodeand Remote-Nodedefinition in the TTGEN configuration file occupy one entry in the table. Each entry structure is 392 bytes long and has the format shown in Table 3-4.

Table 3-4

Node Entries Table

 

 

 

 

 

 

Field Name

Field Description

Field Type

Size

(Bytes)

 

 

 

 

 

 

 

node_num

ZCOM system node number

uns.short

2

 

 

 

 

timeout

Default timeout value for this node

uns.short

2

 

 

 

 

flags

Node status and internal flags

uns.int

4

 

 

 

 

stats

Statistics for this node

struct

16

 

 

 

 

ndshzrvrs

List of node status event receivers

pointer

8

 

 

 

 

nhost

Number of hosts in the host array

uns.short

2

 

 

 

 

spare1

Reserved, not used

uns.short

2

 

 

 

 

spare2

Reserved, not used

int

4

 

 

 

 

host

Host link information

struct [4]

4*88

 

 

 

 

 

NODE_NUM - Node number

 

 

This field contains a unique node number that identifies the entry.

TIMEOUT - Default timeout value for this node

This field contains timeout in seconds for requests sent to this remote node. Most remote ZCOM requests (e.g. ZOPEN, ZTIMR, etc) require a definite response from the remote ZCOM subsystem. If the response is not received within the timeout period specified by this field, error ZENTOUT (-23) is returned to the application program. This field is initialized by TTGEN with the timeout value specified in a Remote-Nodedefinition. This field is zero for a local node entry.

Chapter 3

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