Using the HP-UX libIO Library

I/O Subsystem Terms and Definitions
Legacy Hardware Path
A data structure to store hardware paths (using the format and structure used prior to
HP-UX 11i v3 ) . This structure has 14 elements of 8 bits each.
Agile Hardware Path
A data structure to store hardware paths used for HP-UX 11i v3 and later releases.
This structure has 64 elements of 64 bits each.
I/O Tree
A complete set of I/O modules and devices that constitute a system. The basic
building block of the I/O Tree data structure is the I/O node. There are two views of
the I/O Tree in HP-UX 11i v3: legacy I/O view and agile I/O view.
S_IOTREE
A constant used when searching the kernel I/O system information to indicate that
the legacy I/O view should be searched.
S_IOTREE_EXT
A constant used when searching the kernel I/O system information to indicate that
the agile I/O view should be searched.
I/O node
The basic building block of the I/O Tree. The individual nodes represent elements in
the hardware path. An I/O node has the following characteristics:
• Zero or more siblings
• One parent
• Zero or more child nodes
• Only the root node does not have a parent
Legacy I/O Node
An entry in the I/O Tree representing a physical or virtual I/O device in the legacy
view.
Agile I/O Node
An entry in the I/O Tree representing a physical or virtual I/O device in the agile
view.
Switch Tables
Contain the following entry points for device drivers in the system:
• BDEVSW – block device drivers
• CDEVSW – character device drivers