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61 lines
2.2 KiB
TeX
61 lines
2.2 KiB
TeX
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% $Id$
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% This file is part of the FPC documentation.
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% Copyright (C) 1997, by Michael Van Canneyt
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%
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% The FPC documentation is free text; you can redistribute it and/or
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% modify it under the terms of the GNU Library General Public License as
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% published by the Free Software Foundation; either version 2 of the
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% License, or (at your option) any later version.
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%
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% The FPC Documentation is distributed in the hope that it will be useful,
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% but WITHOUT ANY WARRANTY; without even the implied warranty of
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% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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% Library General Public License for more details.
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%
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% You should have received a copy of the GNU Library General Public
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% License along with the FPC documentation; see the file COPYING.LIB. If not,
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% write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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% Boston, MA 02111-1307, USA.
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%
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\chapter{The DXELOAD unit}
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\section{Introduction}
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The \file{dxeload} unit was implemented by Pierre M\"uller for \dos,
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it allows to load a DXE file (an object file with 1 entry point)
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into memory and return a pointer to the entry point.
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It exists only for \dos.
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\section{Constants, types and variables}
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\subsection{Constants}
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The following constant is the magic number, found in the header of a DXE
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file.
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\begin{verbatim}
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DXE_MAGIC = $31455844;
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\end{verbatim}
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\subsection{Types}
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The following record describes the header of a DXE file. It is used to
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determine the magic number of the DXE file and number of relocations that
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must be done when the object file i sloaded in memory.
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\begin{verbatim}
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dxe_header = record
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magic,
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symbol_offset,
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element_size,
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nrelocs : longint;
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end;
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\end{verbatim}
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\section{Functions and Procedures}
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\begin{functionl}{dxe\_load}{dxeload}
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\Declaration
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function dxe\_load(filename : string) : pointer;
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\Description
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\var{dxe\_load} loads the contents of the file \var{filename} into memory.
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It performs the necessary relocations in the object code, and returns then
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a pointer to the entry point of the code.
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\Errors
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If an error occurs during the load or relocations, \var{Nil} is returned.
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\end{functionl}
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For an example, see the \file{emu387} unit in the RTL.
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