ZCOM Tables and Data Structures

Node Entries Table

FLAGS - Node status and internal flags

This bit-field structure contains bits to maintain state and other internal information about this node. The contents of this field are as follows:

 

FLAGS.event -

Set to 1 if there is at least one application that wants to be

 

 

notified of a status change for the node.

 

 

FLAGS.valid -

Set to 1 if this node entry in the table is valid; that is,

 

 

currently defined and in use.

 

 

FLAGS.status -

Set to 1 if this node is currently UP. The status bit indicates

 

 

whether a remote node is usable. If this bit is not set, the

 

 

LDM will reject all requests to that node with a

 

 

 

ZENDOWN (-61) error. For a local node, the status bit

 

 

indicates that the ZNODE daemon is running properly.

 

FLAGS.local -

Set to 1 if this node entry in the table represents the local

 

 

node.

 

 

 

 

STATS - Statistics for this node

 

 

 

 

This field is a data structure that contains some statistics on the data

 

traffic for this node. The layout of this structure is shown in Table 3-5.

Table 3-5

STATS Data Structure

 

 

 

 

 

 

 

 

 

Field Name

Field Description

 

Field Type

 

Size

 

 

 

 

 

(Bytes)

 

 

 

 

 

icount

Number of incoming messages

uns.int

 

4

 

 

 

 

 

ibytes

Number of incoming bytes

uns.int

 

4

 

 

 

 

 

ocount

Number of outgoing messages

uns.int

 

4

 

 

 

 

 

obytes

Number of outgoing bytes

uns.int

 

4

 

 

 

 

 

 

NDSHZRVRS - Pointer to a list of receivers for node status events.

This field contains a pointer to a linked list of applications to be notified whenever this node changes state. Whenever this node changes state from up-to-down or down-to-up, a node status system event message will be sent to each program in this linked list. That is, those applications that have issued a zevent_rcvr() call to receive node status events. This field will be set to zero if there are no applications to be notified.

Chapter 3

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