########################################################################
##
## Copyright (C) 2010-2025 The Octave Project Developers
##
## See the file COPYRIGHT.md in the top-level directory of this
## distribution or <https://octave.org/copyright/>.
##
## This file is part of Octave.
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## 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
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## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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########################################################################

## -*- texinfo -*-
## @deftypefn  {} {@var{has_terminal} =} __gnuplot_has_terminal__ (@var{term})
## @deftypefnx {} {@var{has_terminal} =} __gnuplot_has_terminal__ (@var{term}, @var{plot_stream})
## Undocumented internal function.
## @end deftypefn

function gnuplot_supports_term = __gnuplot_has_terminal__ (term, plot_stream)

  term = strtrim (term);
  term = lower (strtok (term, " "));

  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

  gnuplot_supports_term = any (strcmp (term, available_terminals));

endfunction
