    indexing
    	description: "[
    		Commonly used console input and output mechanisms.
    		This class may be used as ancestor by classes needing its facilities.
    	]"
    	legal: "See notice at end of class."
    	status: "See notice at end of class."
    	date: "$Date: 2006-01-22 18:25:44 -0800 (Sun, 22 Jan 2006) $"
    	revision: "$Revision: 56675 $"

    class interface
    	CONSOLE

    create {STD_FILES}
    	make_open_stdin (fn: STRING_8)
    			-- Create an unix standard input file.
    		require -- from FILE
    			string_exists: fn /= Void
    			string_not_empty: not fn.is_empty
    		ensure -- from FILE
    			file_named: name = fn
    			exists: exists
    			open_read: is_open_read

    	make_open_stdout (fn: STRING_8)
    			-- Create an unix standard output file.
    		require -- from FILE
    			string_exists: fn /= Void
    			string_not_empty: not fn.is_empty
    		ensure -- from FILE
    			file_named: name = fn
    			exists: exists
    			open_write: is_open_write

    	make_open_stderr (fn: STRING_8)
    			-- Create an unix standard error file.

    feature -- Initialization

    	make_open_stderr (fn: STRING_8)
    			-- Create an unix standard error file.

    	make_open_stdin (fn: STRING_8)
    			-- Create an unix standard input file.
    		require -- from FILE
    			string_exists: fn /= Void
    			string_not_empty: not fn.is_empty
    		ensure -- from FILE
    			file_named: name = fn
    			exists: exists
    			open_read: is_open_read

    	make_open_stdout (fn: STRING_8)
    			-- Create an unix standard output file.
    		require -- from FILE
    			string_exists: fn /= Void
    			string_not_empty: not fn.is_empty
    		ensure -- from FILE
    			file_named: name = fn
    			exists: exists
    			open_write: is_open_write

    feature {ANY} -- Access

    	file_pointer: POINTER
    			-- File pointer as required in C
    			-- (from FILE)

    	separator: CHARACTER_8
    			-- ASCII code of character following last word read
    			-- (from FILE)

    feature -- Access

    	generating_type: STRING_8
    			-- Name of current object's generating type
    			-- (type of which it is a direct instance)
    			-- (from ANY)

    	generator: STRING_8
    			-- Name of current object's generating class
    			-- (base class of the type of which it is a direct instance)
    			-- (from ANY)

    feature -- Comparison

    	frozen deep_equal (some: ANY; other: like arg #1): BOOLEAN
    			-- Are `some' and `other' either both void
    			-- or attached to isomorphic object structures?
    			-- (from ANY)
    		ensure -- from ANY
    			shallow_implies_deep: standard_equal (some, other) implies Result
    			both_or_none_void: (some = Void) implies (Result = (other = Void))
    			same_type: (Result and (some /= Void)) implies some.same_type (other)
    			symmetric: Result implies deep_equal (other, some)

    	frozen equal (some: ANY; other: like arg #1): BOOLEAN
    			-- Are `some' and `other' either both void or attached
    			-- to objects considered equal?
    			-- (from ANY)
    		ensure -- from ANY
    			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.is_equal (other))

    	is_equal (other: like Current): BOOLEAN
    			-- Is `other' attached to an object considered
    			-- equal to current object?
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    		ensure -- from ANY
    			symmetric: Result implies other.is_equal (Current)
    			consistent: standard_is_equal (other) implies Result

    	frozen standard_equal (some: ANY; other: like arg #1): BOOLEAN
    			-- Are `some' and `other' either both void or attached to
    			-- field-by-field identical objects of the same type?
    			-- Always uses default object comparison criterion.
    			-- (from ANY)
    		ensure -- from ANY
    			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.standard_is_equal (other))

    	frozen standard_is_equal (other: like Current): BOOLEAN
    			-- Is `other' attached to an object of the same type
    			-- as current object, and field-by-field identical to it?
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    		ensure -- from ANY
    			same_type: Result implies same_type (other)
    			symmetric: Result implies other.standard_is_equal (Current)

    feature -- Status report

    	conforms_to (other: ANY): BOOLEAN
    			-- Does type of current object conform to type
    			-- of `other' (as per Eiffel: The Language, chapter 13)?
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void

    	count: INTEGER_32 is 1
    			-- Useless for CONSOLE class.

    	end_of_file: BOOLEAN
    			-- Have we reached the end of file?
    		require -- from FILE
    			opened: not is_closed

    	exists: BOOLEAN
    			-- Does file exist?
    		require -- from  IO_MEDIUM
    			True
    		ensure then -- from FILE
    			unchanged_mode: mode = old mode

    	same_type (other: ANY): BOOLEAN
    			-- Is type of current object identical to type of `other'?
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    		ensure -- from ANY
    			definition: Result = (conforms_to (other) and other.conforms_to (Current))

    feature {ANY} -- Status report

    	extendible: BOOLEAN
    			-- May new items be added?
    			-- (from FILE)
    		require -- from  IO_MEDIUM
    			True
    		require -- from  COLLECTION
    			True

    	file_readable: BOOLEAN
    			-- Is there a current item that may be read?
    			-- (from FILE)

    	is_closed: BOOLEAN
    			-- Is file closed?
    			-- (from FILE)

    	is_open_write: BOOLEAN
    			-- Is file open for writing?
    			-- (from FILE)

    	last_character: CHARACTER_8
    			-- Last character read by read_character
    			-- (from IO_MEDIUM)

    	last_double: REAL_64
    			-- Last double read by read_double
    			-- (from IO_MEDIUM)

    	last_integer: INTEGER_32
    			-- Last integer read by read_integer
    			-- (from IO_MEDIUM)

    	last_integer_16: INTEGER_16
    			-- Last 16-bit integer read by read_integer_16
    			-- (from IO_MEDIUM)

    	last_integer_32: INTEGER_32
    			-- Synonymy of last_integer
    			-- (from IO_MEDIUM)

    	last_integer_64: INTEGER_64
    			-- Last 64-bit integer read by read_integer_64
    			-- (from IO_MEDIUM)

    	last_integer_8: INTEGER_8
    			-- Last 8-bit integer read by read_integer_8
    			-- (from IO_MEDIUM)

    	last_natural: NATURAL_32
    			-- Last 32-bit natural read by read_natural
    			-- (from IO_MEDIUM)

    	last_natural_16: NATURAL_16
    			-- Last 16-bit natural read by read_natural_16
    			-- (from IO_MEDIUM)

    	last_natural_32: NATURAL_32
    			-- Synonymy of last_natural
    			-- (from IO_MEDIUM)

    	last_natural_64: NATURAL_64
    			-- Last 64-bit natural read by read_natural_64
    			-- (from IO_MEDIUM)

    	last_natural_8: NATURAL_8
    			-- Last 8-bit natural read by read_natural_8
    			-- (from IO_MEDIUM)

    	last_real: REAL_32
    			-- Last real read by read_real
    			-- (from IO_MEDIUM)

    	last_string: STRING_8
    			-- Last string read
    			-- (from IO_MEDIUM)

    	readable: BOOLEAN
    			-- Is there a current item that may be read?
    			-- (from SEQUENCE)
    		require -- from  ACTIVE
    			True
    		require -- from IO_MEDIUM
    			handle_exists: exists

    feature {ANY} -- Element change

    	append (f: like Current)
    			-- Append a copy of the contents of `f'.
    			-- (from FILE)
    		require -- from SEQUENCE
    			argument_not_void: f /= Void
    		require else -- from FILE
    			target_is_closed: is_closed
    			source_is_closed: f.is_closed
    		ensure -- from SEQUENCE
    			new_count: count >= old count
    		ensure then -- from FILE
    			new_count: count = old count + f.count
    			files_closed: f.is_closed and is_closed

    feature -- Removal

    	dispose
    			-- This is closed by the operating system at completion.
    		require -- from  DISPOSABLE
    			True

    feature -- Duplication

    	copy (other: like Current)
    			-- Update current object using fields of object attached
    			-- to `other', so as to yield equal objects.
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    			type_identity: same_type (other)
    		ensure -- from ANY
    			is_equal: is_equal (other)

    	frozen deep_copy (other: like Current)
    			-- Effect equivalent to that of:
    			--		copy (`other' . deep_twin)
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    		ensure -- from ANY
    			deep_equal: deep_equal (Current, other)

    	frozen deep_twin: like Current
    			-- New object structure recursively duplicated from Current.
    			-- (from ANY)
    		ensure -- from ANY
    			deep_equal: deep_equal (Current, Result)

    	frozen standard_copy (other: like Current)
    			-- Copy every field of `other' onto corresponding field
    			-- of current object.
    			-- (from ANY)
    		require -- from ANY
    			other_not_void: other /= Void
    			type_identity: same_type (other)
    		ensure -- from ANY
    			is_standard_equal: standard_is_equal (other)

    	frozen standard_twin: like Current
    			-- New object field-by-field identical to `other'.
    			-- Always uses default copying semantics.
    			-- (from ANY)
    		ensure -- from ANY
    			standard_twin_not_void: Result /= Void
    			equal: standard_equal (Result, Current)

    	frozen twin: like Current
    			-- New object equal to `Current'
    			-- twin calls copy; to change copying/twining semantics, redefine copy.
    			-- (from ANY)
    		ensure -- from ANY
    			twin_not_void: Result /= Void
    			is_equal: Result.is_equal (Current)

    feature -- Basic operations

    	frozen default: like Current
    			-- Default value of object's type
    			-- (from ANY)

    	frozen default_pointer: POINTER
    			-- Default value of type `POINTER'
    			-- (Avoid the need to write `p'.default for
    			-- some `p' of type `POINTER'.)
    			-- (from ANY)

    	default_rescue
    			-- Process exception for routines with no Rescue clause.
    			-- (Default: do nothing.)
    			-- (from ANY)

    	frozen do_nothing
    			-- Execute a null action.
    			-- (from ANY)

    feature {ANY} -- Obsolete

    	lastchar: CHARACTER_8
    			-- Last character read by read_character
    			-- (from IO_MEDIUM)

    	lastdouble: REAL_64
    			-- Last double read by read_double
    			-- (from IO_MEDIUM)

    	lastint: INTEGER_32
    			-- Last integer read by read_integer
    			-- (from IO_MEDIUM)

    	lastreal: REAL_32
    			-- Last real read by read_real
    			-- (from IO_MEDIUM)

    	laststring: STRING_8
    			-- Last string read
    			-- (from IO_MEDIUM)

    feature -- Input

    	next_line
    			-- Move to next input line on standard input.
    		require -- from FILE
    			is_readable: file_readable

    	read_character
    			-- Read a new character from standard input.
    			-- Make result available in last_character.
    			-- Was declared in CONSOLE as synonym of readchar.
    		require -- from IO_MEDIUM
    			is_readable: readable
    		require else -- from FILE
    			is_readable: file_readable

    	read_double
    			-- Read a new double from standard input.
    			-- Make result available in last_double.
    			-- Was declared in CONSOLE as synonym of readdouble.
    		require -- from IO_MEDIUM
    			is_readable: readable
    		require else -- from FILE
    			is_readable: file_readable

    	read_line
    			-- Read a string until new line or end of file.
    			-- Make result available in last_string.
    			-- New line will be consumed but not part of last_string.
    			-- Was declared in CONSOLE as synonym of readline.
    		require -- from IO_MEDIUM
    			is_readable: readable
    		require else -- from FILE
    			is_readable: file_readable
    		require else
    			is_readable: file_readable
    		ensure -- from IO_MEDIUM
    			last_string_not_void: last_string /= Void

    	read_real
    			-- Read a new real from standard input.
    			-- Make result available in last_real.
    			-- Was declared in CONSOLE as synonym of readreal.
    		require -- from IO_MEDIUM
    			is_readable: readable
    		require else -- from FILE
    			is_readable: file_readable

    	read_stream (nb_char: INTEGER_32)
    			-- Read a string of at most `nb_char' bound characters
    			-- from standard input.
    			-- Make result available in last_string.
    			-- Was declared in CONSOLE as synonym of readstream.
    		require -- from IO_MEDIUM
    			is_readable: readable
    		require else -- from FILE
    			is_readable: file_readable
    		ensure -- from IO_MEDIUM
    			last_string_not_void: last_string /= Void

    	read_word
    			-- Read a new word from standard input.
    			-- Make result available in last_string.
    			-- Was declared in CONSOLE as synonym of readword.
    		require -- from FILE
    			is_readable: file_readable
    		ensure -- from FILE
    			last_string_not_void: last_string /= Void

    	readchar
    			-- Read a new character from standard input.
    			-- Make result available in last_character.
    			-- Was declared in CONSOLE as synonym of read_character.
    		require -- from IO_MEDIUM
    			is_readable: readable
    		require else -- from FILE
    			is_readable: file_readable

    	readdouble
    			-- Read a new double from standard input.
    			-- Make result available in last_double.
    			-- Was declared in CONSOLE as synonym of read_double.
    		require -- from IO_MEDIUM
    			is_readable: readable
    		require else -- from FILE
    			is_readable: file_readable

    	readline
    			-- Read a string until new line or end of file.
    			-- Make result available in last_string.
    			-- New line will be consumed but not part of last_string.
    			-- Was declared in CONSOLE as synonym of read_line.
    		require -- from IO_MEDIUM
    			is_readable: readable
    		require else -- from FILE
    			is_readable: file_readable
    		require else
    			is_readable: file_readable
    		ensure -- from IO_MEDIUM
    			last_string_not_void: last_string /= Void

    	readreal
    			-- Read a new real from standard input.
    			-- Make result available in last_real.
    			-- Was declared in CONSOLE as synonym of read_real.
    		require -- from IO_MEDIUM
    			is_readable: readable
    		require else -- from FILE
    			is_readable: file_readable

    	readstream (nb_char: INTEGER_32)
    			-- Read a string of at most `nb_char' bound characters
    			-- from standard input.
    			-- Make result available in last_string.
    			-- Was declared in CONSOLE as synonym of read_stream.
    		require -- from IO_MEDIUM
    			is_readable: readable
    		require else -- from FILE
    			is_readable: file_readable
    		ensure -- from IO_MEDIUM
    			last_string_not_void: last_string /= Void

    	readword
    			-- Read a new word from standard input.
    			-- Make result available in last_string.
    			-- Was declared in CONSOLE as synonym of read_word.
    		require -- from FILE
    			is_readable: file_readable
    		ensure -- from FILE
    			last_string_not_void: last_string /= Void

    feature -- Output

    	io: STD_FILES
    			-- Handle to standard file setup
    			-- (from ANY)

    	new_line
    			-- Write line feed at end of default output.
    			-- Was declared in CONSOLE as synonym of put_new_line.
    		require -- from IO_MEDIUM
    			extendible: extendible

    	out: STRING_8
    			-- New string containing terse printable representation
    			-- of current object
    			-- Was declared in ANY as synonym of tagged_out.
    			-- (from ANY)

    	print (some: ANY)
    			-- Write terse external representation of `some'
    			-- on standard output.
    			-- (from ANY)

    	put_boolean (b: BOOLEAN)
    			-- Write `b' at end of default output.
    			-- Was declared in CONSOLE as synonym of putbool.
    		require -- from IO_MEDIUM
    			extendible: extendible

    	put_character (c: CHARACTER_8)
    			-- Write `c' at end of default output.
    			-- Was declared in CONSOLE as synonym of putchar.
    		require -- from IO_MEDIUM
    			extendible: extendible

    	put_double (d: REAL_64)
    			-- Write `d' at end of default output.
    			-- Was declared in CONSOLE as synonym of putdouble.
    		require -- from IO_MEDIUM
    			extendible: extendible

    	put_new_line
    			-- Write line feed at end of default output.
    			-- Was declared in CONSOLE as synonym of new_line.
    		require -- from IO_MEDIUM
    			extendible: extendible

    	put_real (r: REAL_32)
    			-- Write `r' at end of default output.
    			-- Was declared in CONSOLE as synonym of putreal.
    		require -- from IO_MEDIUM
    			extendible: extendible

    	put_string (s: STRING_8)
    			-- Write `s' at end of default output.
    			-- Was declared in CONSOLE as synonym of putstring.
    		require -- from IO_MEDIUM
    			extendible: extendible
    			non_void: s /= Void

    	putbool (b: BOOLEAN)
    			-- Write `b' at end of default output.
    			-- Was declared in CONSOLE as synonym of put_boolean.
    		require -- from IO_MEDIUM
    			extendible: extendible

    	putchar (c: CHARACTER_8)
    			-- Write `c' at end of default output.
    			-- Was declared in CONSOLE as synonym of put_character.
    		require -- from IO_MEDIUM
    			extendible: extendible

    	putdouble (d: REAL_64)
    			-- Write `d' at end of default output.
    			-- Was declared in CONSOLE as synonym of put_double.
    		require -- from IO_MEDIUM
    			extendible: extendible

    	putreal (r: REAL_32)
    			-- Write `r' at end of default output.
    			-- Was declared in CONSOLE as synonym of put_real.
    		require -- from IO_MEDIUM
    			extendible: extendible

    	putstring (s: STRING_8)
    			-- Write `s' at end of default output.
    			-- Was declared in CONSOLE as synonym of put_string.
    		require -- from IO_MEDIUM
    			extendible: extendible
    			non_void: s /= Void

    	frozen tagged_out: STRING_8
    			-- New string containing terse printable representation
    			-- of current object
    			-- Was declared in ANY as synonym of out.
    			-- (from ANY)

    feature -- Platform

    	operating_environment: OPERATING_ENVIRONMENT
    			-- Objects available from the operating system
    			-- (from ANY)

    invariant
    		-- from PLAIN_TEXT_FILE
    	plain_text: is_plain_text

    		-- from FILE
    	valid_mode: closed_file <= mode and mode <= append_read_file
    	name_exists: name /= Void
    	name_not_empty: not name.is_empty

    		-- from FINITE
    	empty_definition: is_empty = (count = 0)
    	non_negative_count: count >= 0

    		-- from ANY
    	reflexive_equality: standard_is_equal (Current)
    	reflexive_conformance: conforms_to (Current)

    		-- from ACTIVE
    	writable_constraint: writable implies readable
    	empty_constraint: is_empty implies (not readable) and (not writable)

    		-- from BILINEAR
    	not_both: not (after and before)
    	before_constraint: before implies off

    		-- from LINEAR
    	after_constraint: after implies off

    		-- from TRAVERSABLE
    	empty_constraint: is_empty implies off

    indexing
    	library: "EiffelBase: Library of reusable components for Eiffel."
    	copyright: "Copyright (c) 1984-2006, Eiffel Software and others"
    	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
    	source: "[
    		Eiffel Software
    		356 Storke Road, Goleta, CA 93117 USA
    		Telephone 805-685-1006, Fax 805-685-6869
    		Website http://www.eiffel.com
    		Customer support http://support.eiffel.com
    	]"

    end -- class CONSOLE