# 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 subnormal 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.

Parent topic: Glossary