------------------------------------------------------------------------
-- These package specifications were extracted from IEEE Std 1003.5-1992,
-- IEEE Standard for Information Technology--POSIX Ada Language
-- Interfaces--Part 1: Binding System Application Program Interface,
-- copyright (c)1992 by the Institute of Electrical and Electronics
-- Engineers, Inc.  These package specifications represent only a portion
-- of the document and are not to be interpreteted as the approved
-- consensus standard.  The IEEE Std 1003.5-1992 must be used in
-- conjunction with these package specifications in order to claim
-- conformance.  The IEEE takes no responsibility for and will assume no
-- liability for damages resulting from the reader's misinpretation of
-- said information resulting from its out of context nature.  To order
-- copies of the IEEE Std 1003.5-1992, please contact the IEEE Service
-- Center at 445 Hoes Lane, PO Box 1331, Piscataway, NJ 08855-1331; via
-- phone at 1-800-678-IEEE, 908-981-1393; or via fax at 908-981-9667.
------------------------------------------------------------------------

with POSIX;
with POSIX_Permissions,
     POSIX_Process_Identification;
package POSIX_IO is

	-- common type declarations

	type File_Descriptor is range 0..POSIX.Open_Files - 1;

	Standard_Input	: constant File_Descriptor := 0;
	Standard_Output	: constant File_Descriptor := 1;
	Standard_Error	: constant File_Descriptor := 2;

	type IO_Offset is range @P<implementation defined>;

	subtype IO_Count is IO_Offset range 0 .. IO_Offset'Last;

	subtype Positive_IO_Count is IO_Count range 1 .. IO_Offset'Last;

	type File_Mode is
		(Read_Only, Write_Only, Read_Write, Blocking, Append,
		 Close_On_Exec, Truncate, Exclusive, Control_TTY);

	subtype Open_Mode is File_Mode range Read_Only .. Read_Write;

	subtype File_Control_Mode is
		File_Mode range Read_Only .. Close_On_Exec;

	subtype Settable_File_Control_Mode is
		File_Mode range Blocking .. Close_On_Exec;

	type File_Mode_Set is array (File_Mode range <>) of Boolean;

	subtype File_Control_Mode_Set is File_Mode_Set (File_Control_Mode);

	subtype Settable_File_Control_Mode_Set is
	   File_Mode_Set (Settable_File_Control_Mode);

	type Position is
		(From_Beginning, From_Current_Position, From_End_Of_File);

	-- File open, open_or_create, create, close, duplicate and Create_pipe

	function Open
			(Name	: POSIX.POSIX_String;
			 Mode	: Open_Mode;
			 Blocking	: Boolean := True;
			 Append	: Boolean := False;
			 Truncate	: Boolean := False;
			 Control_TTY	: Boolean := True)
		return File_Descriptor;

	function Open_or_Create
			(Name	: POSIX.POSIX_String;
			 Mode	: Open_Mode;
			 Permissions	: POSIX_Permissions.Permission_Set;
			 Blocking	: Boolean := True;
			 Append	: Boolean := False;
			 Truncate	: Boolean := False;
			 Exclusive	: Boolean := False;
			 Control_TTY	: Boolean := True)
	   return File_Descriptor;

	procedure Close (File : in File_Descriptor);

	function Duplicate (File : File_Descriptor)
		return File_Descriptor;

	function Duplicate
			(File1	: File_Descriptor;
			 File2	: File_Descriptor)
		return File_Descriptor;

	procedure Create_Pipe
			(Read_End	:    out	File_Descriptor;
			 Write_End	:    out	File_Descriptor);

	-- Read and Write

	Pipe_Buffer_Size : constant POSIX.Pipe_Limit_Range :=
			POSIX.Pipe_Limit_Range'First;
			-- minimum implementation guaranteed pipe buffer size

	type IO_Unit is range @P<implementation defined>;

	type IO_Buffer is array (Positive_IO_Count range <>) of IO_Unit;

	procedure Read
			(File	: in	File_Descriptor;
			 Buffer	:    out	IO_Buffer;
			 Last	:    out	IO_Count);

	procedure Write
			(File	: in	File_Descriptor;
			 Buffer	: in	IO_Buffer;
			 Last	:    out	IO_Count);

	generic
		type T is private;
	procedure Generic_Read
			(File	: in	File_Descriptor;
			 Item	:    out	T);

	generic
		type T is private;
	procedure Generic_Write
			(File	: in	File_Descriptor;
			 Item	: in	T);

	-- Seek, File_size, File_Position

	procedure Seek
			(File	: in	File_Descriptor;
			 Offset	: in	IO_Offset;
			 Whence	: in	Position := From_Beginning);

	function File_Size (File : File_Descriptor)
		return IO_Count;

	function File_Position (File : File_Descriptor)
		return IO_Count;

	-- Terminal device operations

	function Is_A_Terminal_Device (File : File_Descriptor)
		return Boolean;

	function Get_Terminal_Device_Name (File : File_Descriptor)
		return POSIX.POSIX_String;

	-- File Control operations

	function Get_File_Control (File : File_Descriptor)
		return File_Control_Mode_Set;

	procedure Set_File_Control
			(File	: in	File_Descriptor;
			 Modes	: in	Settable_File_Control_Mode_Set);

end POSIX_IO;