ZCOM C I/F Library Routines

 

ZLTQUEUE (3X)

PARAMETERS

 

appln

Application number of terminal group.

label

Queue label name.

queuep

Data queue number (or ZCOM error, if negative)

(Return

 

Param)

 

NOTES

The data queue returned should only be used for terminals within the

 

specified application group (there is NO queue ownership validation

 

when it is used in ltqdget and ltqdput). An application value of zero

 

means terminals in ALL application groups. This zero application value

 

allows the queue to be used to store global data for all terminals in the

 

system.

 

Routine zltqueue returns an already assigned queue if the queue label

 

matches a previously assigned queue (in this case the specified

 

application number is not used or validated). This provides a facility to

 

share a data queue between different programs and enables program

 

restartability.

 

The following example illustrates the queue allocation algorithm:

Appln

Appl

 

Queue

 

n

Appln

 

Progra

Queue

Returned

Nmb

Label

m

No.

 

r

 

 

 

 

 

 

A

30

USAGE

1

<-- first allocation

 

 

1

 

 

B

0

GLOBA

2

<-- global allocation

 

 

L

 

 

C

40

CCCCC

1

<-- different appln group

 

 

C

 

 

D

30

USAGE

3

<-- same appln, diff usage

 

 

2

 

 

E

30

USAGE

1

<-- data queue sharing

 

 

1

 

 

Chapter 4

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