%    Copyright (C) 1989, 1996 Aladdin Enterprises.  All rights reserved.
% 
% This file is part of Aladdin Ghostscript.
% 
% Aladdin Ghostscript is distributed with NO WARRANTY OF ANY KIND.  No author
% or distributor accepts any responsibility for the consequences of using it,
% or for whether it serves any particular purpose or works at all, unless he
% or she says so in writing.  Refer to the Aladdin Ghostscript Free Public
% License (the "License") for full details.
% 
% Every copy of Aladdin Ghostscript must include a copy of the License,
% normally in a plain ASCII text file named PUBLIC.  The License grants you
% the right to copy, modify and redistribute Aladdin Ghostscript, but only
% under certain conditions described in the License.  Among other things, the
% License requires that the copyright notice and this notice be preserved on
% all copies.

% $Id: gs_epsf.ps $
% Allow the interpreter to recognize MS-DOS EPSF file headers, and skip to
% the PostScript section of the file.

/.runnoepsf /run load def
/.epsfheader <C5D0D3C6> def
/run
 { dup type /filetype ne { (r) file } if
		% Check for MS-DOS EPSF file (see Red Book p. 729).
   true exch 0 1 3
    {		% Stack: true file index
      1 index read dup { pop dup .epsfheader 3 index get eq } if
       { pop pop }	% if matched, don't need the character
       {	% unread characters (wasn't EPSF)
	 2 index exch unread     % unread mismatch character
	 dup {   % loop unreading backwards in .epsfheader
	   1 sub dup .epsfheader exch get 2 index exch unread
	 } repeat pop
	 exch not exch exit	% change true to false
       }
      ifelse
    }
   for exch	% Stack: file true/false
    {		% This block is executed if the file is MS-DOS EPSF.
		% Build up the little-endian byte offset and length.
      2
	{ 1 0 4
	   { 2 index read not { pop exit } if % if EOF, let error happen
	     2 index mul add exch 256 mul exch
	   }
	  repeat exch pop exch
	}
      repeat
		% Stack: offset length file
		% Use flushfile to skip quickly to the start of the
		% PostScript section.
      dup 4 -1 roll 12 sub () /SubFileDecode filter flushfile
		% Now interpret the PostScript.
      exch () /SubFileDecode filter cvx .runexec
    }
    { .runnoepsf
    }
   ifelse
 } odef