Glossary P
- packed record
- A record that starts on an arbitrary byte boundary; each field starts
in the next unused byte. Contrast with
naturally aligned record.
- pad
- The filling of unused positions in a field or character string with
dummy data (such as zeros or blanks).
- parallel processing
- The simultaneous use of more than one processor (CPU)
to execute a program.
- parameter
- Can be either of the following:
- In general, any quantity of interest in a given situation; often used
in place of the term "argument".
- A Fortran 95/90 named constant.
- parent process
- A process that initiates and controls another process (child). The parent
process defines the environment for the child process. Further, the parent
process can suspend or terminate without affecting the child process. See also
child process.
- parent window
- A window that has one or more child windows. See also
child window.
- pathname
- On Windows, Tru64 UNIX, and Linux systems, the
path from the root directory to a subdirectory or file. See also
root.
- pipe
- On Windows, Tru64 UNIX, and Linux systems, a
connection that allows one program to get its input directly from the output of
another program.
- platform
- A combination of operating system and hardware that provides a distinct
environment in which to use a software product (for example, Tru64 UNIX on
Alpha processors).
- pointer
- Is one of the following:
- A Fortran 95/90 pointer
A data object that has the POINTER attribute. To be referenced or defined,
it must be "pointer-associated" with a target (have storage space
associated with it). If the pointer is an array, it must be pointer-associated
to have a shape. See also pointer association.
- A Compaq Fortran pointer
A data object that contains the address of its paired variable. This is also
called an integer pointer or a Cray® pointer.
- pointer assignment
- The association of a pointer with a target by the execution of a pointer
assignment statement or the execution of an assignment statement for a
data object of derived type having the pointer as a subobject.
- pointer
association
- The association of storage space to a Fortran 95/90 pointer by means of
a target. A pointer is associated with a target after pointer assignment
or the valid execution of an ALLOCATE statement.
- precision
- The number of significant digits in a real number. See also
double-precision
constant, kind
type parameter, and single-precision
constant.
- primary
- The simplest form of an expression. A primary can be any of the following
data objects:
- A constant
- A constant subobject (parent is a constant)
- A variable (scalar, structure, array, or pointer; an array cannot be
assumed size)
- An array constructor
- A structure constructor
- A function reference
- An expression in parentheses
- primary key
- On OpenVMS systems, the required key within the data records of an
indexed file. This key is used to determine the placement of records
within the file and to build the primary index.
- primary thread
- The initial thread of a process. Also called the main thread or thread
1. See also thread.
- procedure
- A computation that can be invoked during program execution. It can
be a subroutine or function, an internal, external, dummy or module procedure,
or a statement function. A subprogram can define more than one procedure
if it contains an ENTRY statement. See also subprogram.
- procedure
interface
- The statements that specify the name and characteristics of a procedure,
the name and attributes of each dummy argument, and the generic identifier
(if any) by which the procedure can be referenced. If these properties
are all known to the calling program, the procedure interface is explicit;
otherwise it is implicit.
- process object
- A virtual address space, security profile, a set of threads that execute
in the address space of the process, and a set of resources visible to
all threads executing in the process. Several thread objects can be associated
with a single process.
- program unit
- The fundamental component of an executable program. A sequence of statements
and comment lines. It can be a main program, a module, an external subprogram,
or a block data program unit.