|   | Section 8.10:Input/Output Classes
 |  | 
  
 
This section of the required library contains definitions of those
abstractions and classes which model input and output operations to files
(whether binary or text) and standard channels.
  - Abstract Classes - 
      - $IN_DEVICE - this abstraction models
        all of those devices which are capable of sending data to a
      program.
- $OUT_DEVICE - this abstraction
        models all of those devices which are capable of accepting data from a
        program.
- $INOUT_DEVICE - this abstraction
        models all of those devices which are capable of carrying out two
        communication with a program.
- $FILES - this abstraction models input
        and output from file objects.
- $FILE_CURSORS - this abstraction
        models a sliding window on the contents of a file.
 
- Immutable Classes - 
      - FILE_MODES - this enumeration class
        implements the various modes in which a file may be opened.
- FILE_LOCS - this enumeration class
        implements the two fixe and one alterable file locations from which
        position searching may be made.
- CONDITIONALS - this enumeration
        class provides the pre-processing primitives associated with the SOURCE class.
 
- Reference Classes - 
      - PROGRAM_ARGS - this class implements
        various forms of communication to command lines, configuration files,
        etc, registering handlers if needed by some program class.
- IN - this class implements communication with
        the standard input channel as defined by the execution
      environment.
- OUT - this class implements communication
        with the standard output channel as defined by the execution
        environment.
- ERR - this class implements communication
        with the standard error channel as defined by the execution
        environment.
- BIN_FILE - this class implements a
        binary file, the contents of which is a stream of octets with no
        semantics attaching insofar as the external environment is aware.
- TEXT_FILE - this class implements a
        text file, the contents of which is a stream of text characters which
        may or may not be structured into lines/pages.
- BIN_FILE_CURSOR - this class
        implements a buffer which provides a sliding window on the contents of
        an associated binary file.
- TEXT_FILE_CURSOR - this class
        implements a buffer which provides a sliding window on the contents of
        an associated text file.
- PIPE - this class implements a sequential
        communication channel between two programs, one writing and the other
        reading.
- SOURCE - this class implements a source of
        lines of text which may either be subject to conditional
        pre-processing (see  CONDITIONALS) or
        not as required.
- REPORTER - this class implements a
        reporter of error and warning messages.  It is intended to be used
        with message files.
 
 
  
    
      | Comments
        or enquiries should be made to Keith Hopper. Page last modified:  Friday, 10 March 2000.
 |   |