HP UX 11i v1 I/O Cards manual ZLU Tables, Individual ZLU Entries

ZCOM Tables and Data Structures

ZLU Tables

ZLU Tables

The ZCOM logical unit table relates a terminal device or a program queue with a number or logical unit. The ZCOM logical units are called ZLUs to distinguish them from the HP-UX logical units (LUs).

Each ZLU entry structure contains 40 bytes of data.

The ZLU table is split into two logically distinct parts. The first part is the physical terminal area, and the second the dynamically assignable program ZLUs. The latter are used for program input queues. The ZLUs can be mapped so that a particular ZLU can point to any other ZLU.

Individual ZLU Entries

The individual ZLU data structure (zlu_type) layout is shown in Table 3-7.

Table 3-7	Individual ZLU Data Structure (zlu_type)
Field Name	Field Description	Field Type	Size
			(Bytes)
zcksum	ZLU checksum	uns.short	2
zlttype	ZLU type	uns.short	2
zpoint	ZLU pointer or mapped node nmbr	uns.short	2
zmpzlu	Mapped ZLU number	uns.short	2
zmpzcs	Mapped ZLU checksum	uns.short	2
zlname	ZLU Name (8 bytes)	char [8]	8
zowner	PID number of owner	uns.short	2
ztimer	Timeout interval (seconds)	short	2
zclock	Timeout clock	short	2
zlock	ZLU lock pointer	pointer	8
refcnt	Lock reference count	unns.int	4
spare1	Reserved, not used	int	4

Chapter 3 57