F
FAT
  See file allocation table.
f ile allocation table (FAT)
  A table used by DOS to allocate space for a file. This allocation method limits file names to an 8.3 form. FAT partitions are less efficient in use of space and speed than HPFS and NTFS partitions. See high performance file system, NT file system.
file descriptor
  A small positive integer that the system uses instead of the file name to identify an open file.
file extension
  The three-character suffix appended to a file name in the FAT file-naming convention. The extension is optional in some file systems. The compilers use file extensions to determine the source type of the file.
file scope
  A name declared outside all blocks and classes has file scope and can be used after the point of declaration in a source file.
file-scoped action
  Distinguished from a project-scoped action in that it is invoked on files. Only file-scoped actions can participate in a project build.
first element
  The element visited first in an iteration over a collection. Each collection has its own definition for first element. For example, the first element of a sorted set is the element with the smallest value.
flat collection
  A collection that has no hierarchical structure.
float constant
  A number containing a decimal point, an exponent, or both. The exponent contains an e or E, an optional sign (+ or -) and one or more digits (0 through 9). IBM.
folder
  A directory.
font
  A particular size and style of typeface that contains definitions of character sets, marker sets, and pattern sets.
for statement
  A looping statement that contains the word for followed by a list of expressions enclosed in parentheses (the condition) and a statement (the action). Each expression in the parenthesized list is separated by a semicolon. You can omit any of the expressions, but you cannot omit the semicolons.
frame
  (1) A complete television picture that is composed of two scanned fields, one of the even lines and one of the odd lines. In the NTSC system, a frame has 525 horizontal lines and is scanned in 1/30th of a second. See NTSC. (2) A border around a window.
frame extension
  A control that can be added to a frame window.
frame number
  (1) The number used to identify a frame. (2) The location of a frame on a videodisc or in a video file. On videodisc, frames are numbered sequentially from 1 to 54,000 on each side and can be accessed individually; on videotape, the numbers are assigned by way of the SMPTE time code.
frame rate
  The speed at which frames are scanned. For a videodisc player, the speed at which frames are scanned is 30 frames per second for NTSC video. For most videotape devices, the speed is 24 frames per second. See NTSC.
frame window
  In the IBM Open Class library, a window that an application uses as the base when constructing a main window, dialog box, or message box.
free store
  Dynamically allocated memory. In the C++ language, new is used to allocate free store for objects and delete is used to deallocate it. In C, the malloc family of functions is used. There are also system APIs for dynamic memory allocation. Synonymous with program heap.
friend class
  A class in which all the member functions are granted access to the private and protected members of another class. It is named in the declaration of the other class with the prefix friend.
friend function
  A function that is granted access to the private and protected parts of a class. It is named in the declaration of the class with the prefix friend.
full-motion video
  (1) Video playback at 30 frames per second on NTSC signals. (2) A digital video compression technique that operates in real time.
function
  A named group of statements that can be called and evaluated and can return a value to the calling statement. IBM. See member function.
function call
  An expression that moves the path of execution from the current function to a specified function and evaluates to the return value provided by the called function. A function call contains the name of the function to which control moves and a parenthesized list of values. IBM.
function declarator
  The part of a function definition that names the function, provides additional information about the return value of the function, and lists the function parameters. IBM.
function definition
  The complete description of a function. A function definition contains an optional storage class specifier, an optional type specifier, a function declarator, optional parameter declarations, and a block statement (the function body).
function prototype
  A function declaration that provides type information for each parameter. It is the first line of the function (header) followed by a semicolon (;). The declaration is required by the compiler at the time that the function is declared, so that the compiler can check the type.
function scope
  The capacity to be used anywhere in a function. Labels that are declared in a function have function scope.
function template
  A description of how to construct a set of related individual functions.