Glossary U

ultimate component

For a derived type or a structure, a component that is of intrinsic type or has the ALLOCATABLE or POINTER attribute, or an ultimate component of a component that is a derived type and does not have the ALLOCATABLE or POINTER attribute.

unary operator

An operator that operates on one operand. For example, the minus sign in -A and the .NOT. operator in .NOT. (J .GT. K).

undeferred task

A task for which execution is not deferred with respect to its generating task region; that is, its generating task region is suspended until execution of the undeferred task has finished.

undefined

For a data object, the property of not having a determinate value.

underflow

An error condition occurring when the result of an arithmetic operation yields a result that is smaller than the minimum value in the range of a data type. For example, in unsigned arithmetic, underflow occurs when a result is negative. See also denormalized number.

unformatted data

Data written to a file by using unformatted I/O statements; for example, binary numbers.

unformatted I/O statement

An I/O statement that does not contain format specifiers and therefore does not translate the data being transferred. Contrast with formatted I/O statement.

unformatted record

A record that is transmitted in internal format between internal and external storage.

unit identifier

The identifier that specifies an external unit or internal file. The identifier can be any one of the following:

• An integer expression whose value must be zero or positive

• An asterisk (*) that corresponds to the default (or implicit) I/O unit

• The name of a character scalar memory reference or character array name reference for an internal file

Also called a device code, or logical unit number.

unspecified storage unit

A unit of storage for holding a pointer or a scalar that is not a pointer and is of type other than default integer, default character, or default real.

upper bounds

See bounds.

use association

The process by which the entities in a module are made accessible to other scoping units (through a USE statement in the scoping unit).

user-defined assignment

See defined assignment.

user-defined operator

See defined operation.

user-defined type

See derived type.