ISO2002 The Function-ID Paragraph

The Function-ID paragraph specifies the name by which a function is identified and assigns selected attributes to that function.

General Format
Format 1 (definition):
    FUNCTION-ID. user-function-name-1 [ AS literal-1 ].
Format 2 (prototype):
    FUNCTION-ID. function-prototype-name-1 [ AS literal-1 ] IS PROTOTYPE.
Syntax Rules
  1. Literal-1 must be an alphanumeric literal and must not be a figurative constant.
General Rules
    Format 1
  1. User-function-name-1 names the function declared by this function definition. However, literal-1, if specified, is the name of the function that is externalized to the operating environment.
  2. Format 2
  3. Function-prototype-name-1 names the function prototype declared by this definition. However, literal-1, if specified, is the name of the function prototype that is externalized to the operating environment.