NonStop System Glossary

page
See memory page.
PAL
See privileged architecture library (PAL).
PALCode
TNS/E system firmware that uses the privileged architecture library (PAL). PALCode provides a
mechanism to implement low-level hardware support functions that are privileged, atomic operations
and that require long instruction sequences.
Parallel Library TCP/IP
An HP product that provides increased performance and scalability over conventional Transmission
Control Protocol/Internet Protocol (TCP/IP). Parallel Library TCP/IP coexists with conventional
TCP/IP on NonStop systems. See also HP NonStop TCP/IP.
PARAM
A TACL command and a Subsystem Control Facility (SCF) command you can use to create a
parameter and give it a value. The TACL process stores the values of parameters assigned by the
PARAM command and sends the values to applications that request parameter values.
parent directory
A particular directory in the hierarchy of directories within a file system. The parent directory for
a directory contains an entry for that specific directory and is identified in that directory as the
directory immediately above it in the hierarchy. The parent directory for a file contains an entry
for that file.
parent process
The process that created a given process or (if the creating process has stopped) a process that
has inherited a given process. See also child process.
parent process ID
In the Open System Services (OSS) environment, an attribute of a child process determined by the
parent process. The parent process ID is the OSS process ID of the current parent process.
parity
The use of an extra bit on memory chips that serves as a checksum so the operating system can
detect if single-bit memory errors are occurring.
passthrough terminator
See SCSI passthrough terminator.
path
The route between a processor and a subsystem. If a subsystem is configured for fault tolerance,
it has a primary path (from the primary processor) and a backup path (from the backup processor).
path prefix
In the Open System Services (OSS) environment, a pathname with an optional final slash (/)
character that refers to a directory.
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