User Guide
Ampex 1308911-02 A-7
Glossary and Acronyms Glossary
Interface Parameters
A set of attributes that control the characteristics of an open interface 
to a device. Most interface parameters are configured as static device 
special file attributes. Others, such as the data block size, can be 
changed on the fly after the device is opened.
ioctl A system call that performs a device I/O control operation on behalf of 
the calling program.
Kilobyte (KB) 2
10
 (1024) bytes.
Layout A format parameter that determines how partitions are allocated with 
respect to system zones.
Load Establishes the position on tape, enabling the DST drive to accept 
medium access commands. Sometimes synonymous with Insert. See 
Insert.
Logical Data Block See Data Block.
Logical Data Block Number (LDBN)
The ordinal number that identifies a data block within a file section or 
a partition.
Longitudinal (Linear) Tracks
Three lengthwise tracks used to record servo, logical address, and 
physical address information about each block of helically recorded 
data.
Megabyte (MB) 2
20
 (1024*1024 or 1,048,576) bytes.
mtio Interface A device interface compatible with the standard mtio device. The 
mtio-compatible interface includes device special files that perform 
default operations when the device is opened or closed.
Off-line The state in which a tape is not loaded. A tape that is off-line must be 
put on-line before data can be transferred to or from it. For a device, 
refers to the state in which its communication channel to other devices 
is not open and the device is not responding normally to 
communications over that channel.
On-line The state in which a tape is loaded and ready for data transfer. For a 
device, refers to the state in which its communication channel to other 
devices is open and the device is able to respond to communications. 
For example, a DST tape drive is on-line when it can receive 
commands from a host computer and respond to those commands.










