The following listing contains the interface of the DosUnix unit.
This unit is there to overcome some of those differences between Dos and Unix systems that are not automatically hidden by GPC and the Run Time System. Currently features translation of bash style input/output redirections (foo 2>&1) into redir calls for DJGPP (redir -eo foo) and a way to read files with Dos CR/LF pairs on any system.
When necessary, new features will be added to the unit in future releases.
{ Some routines to support writing programs portable between Dos and
Unix. Perhaps it would be a good idea not to put features to make
Dos programs Unix-compatible (shell redirections) and vice versa
(reading Dos files from Unix) together into one unit, but rather
into two units, DosCompat and UnixCompat or so -- let's wait and
see, perhaps when more routines suited for this/these unit(s) will
be found, the design will become clearer ...
Copyright (C) 1998-2005 Free Software Foundation, Inc.
Author: Frank Heckenbach <frank@pascal.gnu.de>
This file is part of GNU Pascal.
GNU Pascal is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published
by the Free Software Foundation; either version 2, or (at your
option) any later version.
GNU Pascal is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
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As a special exception, if you link this file with files compiled
with a GNU compiler to produce an executable, this does not cause
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License. This exception does not however invalidate any other
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{$gnu-pascal,I-}
{$if __GPC_RELEASE__ < 20030412}
{$error This unit requires GPC release 20030412 or newer.}
{$endif}
unit DosUnix;
interface
uses GPC;
{ This function is meant to be used when you want to invoke a system
shell command (e.g. via Execute or Exec from the Dos unit) and
want to specify input/output redirections for the command invoked.
It caters for the different syntax between DJGPP (with the redir
utility) and other systems.
To use it, code your redirections in bash style (see the table
below) in your command line string, pass this string to this
function, and the function's result to Execute or the other
routines.
The function translates the following bash style redirections
(characters in brackets are optional) into a redir call under Dos
systems except EMX, and leave them unchanged under other systems.
Note: redir comes with DJGPP, but it should be possible to
install it on other Dos systems as well. OS/2's shell, however,
supports bash style redirections, I was told, so we don't
translate on EMX.
[0]< file redirect standard input from file
[1]>[|] file redirect standard output to file
[1]>> file append standard output to file
[1]>&2 redirect standard output to standard error
2>[|] file redirect standard error to file
2>> file append standard error to file
2>&1 redirect standard error to standard output
&> file redirect both standard output and standard
error to file }
function TranslateRedirections (const Command: String) = s:
TString;
{ Under Unix, translates CR/LF pairs to single LF characters when
reading from f, and back when writing to f. Under Dos, does
nothing because the run time system alrady does this job. In the
result, you can read both Dos and Unix files, and files written
will be Dos. }
procedure AssignDos (var f: AnyFile; const FileName: String);
{ Translates a character from the "OEM" charset used under Dos to
the ISO-8859-1 (Latin1) character set. }
function OEM2Latin1 (ch: Char): Char;
function OEM2Latin1Str (const s: String) = r: TString;
{ Translates a character from the ISO-8859-1 (Latin1) character set
to the "OEM" charset used under Dos. }
function Latin12OEM (ch: Char): Char;
function Latin12OEMStr (const s: String) = r: TString;