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

Chapter 1 53
Glossary of Terms
PURGE command is also used to delete an account structure entry such as a
user name, group name, or an account.
query A data retrieval request.
queue A list that allows additions at one end and deletions at the opposite end.
Items in a queue are usually processed on the first in, first out (FIFO)
principle, in that the first item entered is the first item to be processed. For
example, the output produced by a program is generally stored on disk in a
queue until a printer becomes available. As each output is printed the next
in priority is selected and processed.
quiet mode A session mode in which messages sent from other jobs or sessions to a
terminal are not displayed. Users control quiet mode with the SETMSG
command. To determine who is running quietly, execute the SHOWJOB
command. Those sessions not receiving messages are indicated by the
word QUIET in the third column of the listing. A WARN message from the
system console overrides quiet mode and should be used for all critical
communication, such as informing the user of an impending system
shutdown.
random access The direct access to data stored in a device. For example, if a user or
program requires the 17th record in a file stored on random access media,
that record may be selected for the read/write operation without scanning
the preceding 16 records. Typical random access storage devices include
main memory and disk drives.
random access memory (RAM) A part of memory that contains information that is
temporarily stored in the computer. When the computer is turned off,
random access memory is erased. The opposite of read-only memory.
read To request and accept input data from a source.
read-only memory (ROM) The memory used for storing firmware. A ROM contains
information that cannot be modified and is not erased when the computer
is turned off. The opposite of random access memory.
ready state The condition of an input spoolfile when it is available for access by the
spooler program or user. READY output spoolfiles are complete files waiting
to be printed. They may also be manipulated with the SPOOK utility.
real time An operating system feature that enables it to react very quickly to
external and internal events as they occur.
record A collection of fields or related data treated as a unit, residing in a file. A
contiguous group of bytes whose structure is known by the file system.
recognizing a disk See mounting.
record width The amount of data that is transmitted to and from a device at one time.
For example, the standard record width for terminals is 80 bytes. The
record width for disk devices is 128 words.
recursion The ability of a procedure or function to call itself.
redo file An MPE/iX disk file containing the commands entered by the user.