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The following listing contains the interface of the Printer unit.
This unit provides printer access, compatible to BP's Printer
unit, for Dos (using printer devices) and Unix systems (using
printer utilities).
For BP compatibility, the variable Lst is provided, but for
newly written programs, it is recommended to use the
AssignPrinter procedure on a text file, and close the file
when done (thereby committing the printer job). This method allows
for sending multiple printer jobs in the same program.
{ BP compatible printer unit with extensions
Copyright (C) 1998-2003 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
along with GNU Pascal; see the file COPYING. If not, write to the
Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA.
As a special exception, if you link this file with files compiled
with a GNU compiler to produce an executable, this does not cause
the resulting executable to be covered by the GNU General Public
License. This exception does not however invalidate any other
reasons why the executable file might be covered by the GNU
General Public License. }
{$gnu-pascal,I-}
{$if __GPC_RELEASE__ < 20030303}
{$error This unit requires GPC release 20030303 or newer.}
{$endif}
unit Printer;
interface
uses GPC {$ifndef __OS_DOS__}, Pipe {$endif};
var
{ Dos-like systems: writing to a printer device }
{ The file name to write printer output into }
PrinterDeviceName: PString = @'prn';
{ Unix-like systems: printing via a printer program }
{ The file name of the printer program. If it contains a '/', it
will be taken as a complete path, otherwise the file name will
be searched for in the PATH with FSearchExecutable. }
PrinterCommand: PString = @'lpr';
{ Optional command line parameters for the printer program.
Ignored when nil. }
PrinterArguments: PPStrings = nil;
{ How to deal with the printer spooler after the printer pipe is
closed, cf. the Pipe unit. }
PrinterPipeSignal : Integer = 0;
PrinterPipeSeconds: Integer = 0;
PrinterPipeWait : Boolean = True;
{ Text file opened to default printer }
var
Lst: Text;
{ Assign a file to the printer. Lst will be assigned to the default
printer at program start, but other files can be assigned to the
same or other printers (possibly after changing the variables
above). SpoolerOutput, if not Null, will be redirected from the
printer spooler's standard output and error. If you use this, note
that a deadlock might arise when trying to write data to the
spooler while its output is not being read, though this seems
quite unlikely, since most printer spoolers don't write so much
output that could fill a pipe. Under Dos, where no spooler is
involved, SpoolerOutput, if not Null, will be reset to an empty
file for compatibility. }
procedure AssignPrinter (var f: AnyFile; var SpoolerOutput:
AnyFile);