MPE/iX Glossary of Terms and Acronyms (32650-90887)

Chapter 1 21
Glossary of Terms
CRC-CCITT An error detection scheme defined by the Comite Consultatif International
Telephonique et Telegraphique (CCITT).
CRC-16 An error detection scheme used in data communications.
create volumes capability (CV capability) The ability to define and access nonsystem
domain disks with the NEWSET command of VOLUTIL.PUB.SYS (use
NEWVSET command for private volumes on MPE V/E). Users and accounts
assigned CV capability are automatically given use volumes (UV)
capability.
cursor 1. A flashing rectangle or blinking underline character on a display
screen. It marks the position where text or data can be entered,
changed, or deleted.
2. In HP SQL, the pointer to one tuple in a set of tuples from an
application program.
customer engineer (CE) A Hewlett-Packard field representative responsible for the
installation, troubleshooting, and maintenance of computer hardware and
operating systems.
custom performance consulting Using an outside performance expert to locate and
evaluate performance problems.
cyclic redundancy check (CRC) An error detection scheme in which the checking
character is generated by taking the remainder after dividing all the
serialized bits in a block of data by a predetermined binary number. An
equal comparison indicates no errors, while an unequal comparison
indicates an error in the transmission.
cylinder A portion of a disk pack that consists of vertically aligned tracks on each
disk platter within the pack. The first track on the first platter is directly
above the first track on the second platter, which is aligned with the first
track on the third platter, and so on. These tracks, taken together, are
considered a cylinder. Therefore, cylinder 1 refers to track 1 on each of the
platters in the disk.
daisy wheel printer A printer that forms characters by striking metal or plastic images
of characters against a ribbon onto paper. The name comes from the shape
of the print wheel, which looks like a daisy.
database (DB) A collection of logically related data files, and structural information
about the data and/or files.
database management system (DBMS) A software package designed to protect the
consistency and security of data in computer-stored files (databases). It
allows a user to define a database structure and manipulate the contents
by storing, retrieving, deleting, modifying, and sorting data.
data cache A high-speed CPU cache implemented on the 900 Series HP 3000. It
operates in parallel with the instruction cache. Data is transferred by load
and store instructions between the general purpose registers of the
execution unit and the data cache. It is a write-to cache, so the main
memory modules are updated only as required. See instruction cache.