INTERFACE OSError_ux;

(***************************************************************************)
(*                      Copyright (C) Olivetti 1989                        *)
(*                          All Rights reserved                            *)
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(* upon this software are permitted to any person, provided this same      *)
(* copyright notice and the following Olivetti warranty disclaimer are     *) 
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(* derivative work therefrom made by any person.                           *)
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(* This software is made available AS IS and Olivetti disclaims all        *)
(* warranties with respect to this software, whether expressed or implied  *)
(* under any law, including all implied warranties of merchantibility and  *)
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(***************************************************************************)

IMPORT Text;
IMPORT Ctypes;

IMPORT OSError;


REVEAL
  OSError.T = BRANDED REF Ctypes.int;
(* Unix error codes are just integers *)

PROCEDURE CodeToText(error: Ctypes.int): Text.T RAISES {};
(* Returns error message or "unknown error" if 'error' is not a valid error
code. *)

PROCEDURE Raise() RAISES {OSError.E};
(* Only to be called when
1) 'Unix.errnoMutex' is locked
2) a call to the Unix kernel or Unix library has just failed and set 'errno'
This procedure reads 'errno', sets up a 'OSError.T' value and then raises
'OSError.E' with that value as its argument *)

PROCEDURE Return(): OSError.T RAISES {};
(* Only to be called when
1) 'Unix.errnoMutex' is locked
2) a call to the Unix kernel or Unix library has just failed and set 'errno'
This procedure reads 'errno', sets up a 'OSError.T' value and returns it *)

END OSError_ux.