--- /dev/null
+## Copyright (C) 2010-2012 Ben Abbott
+##
+## 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{has_terminal} =} __gnuplot_has_terminal__ (@var{terminal})
+## Undocumented internal function.
+## @end deftypefn
+
+## Author: Ben Abbott <bpabbott@mac.com>
+## Created: 2010-09-13
+
+function gnuplot_supports_term = __gnuplot_has_terminal__ (term, plot_stream)
+ term = deblank (term);
+ n = find (term == " ", 1);
+ if (! isempty (n))
+ term = term(1:n-1);
+ endif
+ if (__gnuplot_has_feature__ ("variable_GPVAL_TERMINALS"))
+ if (nargin < 2)
+ plot_stream = __gnuplot_open_stream__ (2);
+ endif
+ available_terminals = __gnuplot_get_var__ (plot_stream, "GPVAL_TERMINALS");
+ available_terminals = regexp (available_terminals, '\w+', "match");
+ if (nargin < 2 && ! isempty (plot_stream))
+ pclose (plot_stream(1));
+ if (numel (plot_stream) > 1)
+ pclose (plot_stream(2));
+ endif
+ if (numel (plot_stream) > 2)
+ waitpid (plot_stream(3));
+ endif
+ endif
+ else
+ ## Gnuplot 4.0 terminals. No new terminals were added until 4.4 which
+ ## allows the list of terminals to be obtained from GPVAL_TERMINALS.
+ available_terminals = {"aifm", "aqua", "canvas", "cgm", "corel", ...
+ "dumb", "dxf", "eepic", "emf", "epslatex", ...
+ "epson_180dpi", "fig", "gif", "gnugraph", ...
+ "gpic", "hp2623A", "hp2648", "hp500c", ...
+ "hpgl", "hpljii", "hppj", "imagen", "jpeg", ...
+ "latex", "mf", "mif", "mp", "pbm", "pdf", ...
+ "pm", "png", "postscript", "pslatex", ...
+ "pstex", "pstricks", "qms", "regis", "rgip", ...
+ "svg", "texdraw", "tgif", "tkcanvas", ...
+ "tpic", "windows", "x11", "xlib", "xterm"};
+ endif
+ gnuplot_supports_term = any (strcmpi (available_terminals, term));
+endfunction
+