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/* isatty() replacement.
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Copyright (C) 2012 Free Software Foundation, Inc.
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This program is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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/* This replacement is enabled on native Windows. */
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/* Get declarations of the Win32 API functions. */
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#define WIN32_LEAN_AND_MEAN
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#include "msvc-inval.h"
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/* Get _get_osfhandle(). */
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#include "msvc-nothrow.h"
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/* Optimized test whether a HANDLE refers to a console.
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See <http://lists.gnu.org/archive/html/bug-gnulib/2009-08/msg00065.html>. */
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#define IsConsoleHandle(h) (((intptr_t) (h) & 3) == 3)
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#if HAVE_MSVC_INVALID_PARAMETER_HANDLER
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_isatty_nothrow (int fd)
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result = _isatty (fd);
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# define _isatty_nothrow _isatty
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/* Determine whether FD refers to a console device. Return 1 if yes.
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Return 0 and set errno if no. (ptsname_r relies on the errno value.) */
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HANDLE h = (HANDLE) _get_osfhandle (fd);
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if (h == INVALID_HANDLE_VALUE)
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/* _isatty (fd) tests whether GetFileType of the handle is FILE_TYPE_CHAR.
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But it does not set errno when it returns 0. */
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if (_isatty_nothrow (fd))
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if (IsConsoleHandle (h))