## Copyright (C) 2005, 2006, 2007 Søren Hauberg
## 
## This file is part of Octave.
##
## Octave 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 3 of the License, or (at
## your option) any later version.
##
## Octave 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 Octave; see the file COPYING.  If not, see
## <http://www.gnu.org/licenses/>.

## -*- texinfo -*-
## @deftypefn {Function File} {@var{entries} =} tar (@var{tarfile}, @var{files}, @var{root})
## Pack @var{files} @var{files} into the TAR archive @var{tarfile}.  The
## list of files must be a string or a cell array of strings.
##
## The optional argument @var{root} changes the relative path of @var{files}
## from the current directory.
##
## If an output argument is requested the entries in the archive are
## returned in a cell array.
## @seealso{untar, gzip, gunzip, zip, unzip}
## @end deftypefn

## Author: Søren Hauberg <hauberg@gmail.com>

function entries = tar (tarfile, files, root)

  if (nargin == 2 || nargin == 3)

    if (nargin == 2)
      root = ".";
    endif

    ## Test type of input
    if (ischar (files))
      files = cellstr (files);
    endif

    if (ischar (tarfile) && iscellstr (files) && ischar (root))

      cmd = sprintf ("tar -c -v -f %s -C %s %s", tarfile, root,
		     sprintf (" %s", files{:}));

      [status, output] = system (cmd);

      if (status == 0)
	if (nargout > 0)
	  if (output(end) == "\n")
	    output(end) = [];
	  endif
          entries = cellstr (split (output, "\n"));
	  entries = entries';
	endif
      else
	error ("tar: tar exited with status = %d", status);
      endif
    
    else
      error ("tar: expecting all arguments to be character strings");
    endif

  else
    print_usage("tar");
  endif

endfunction
