/* File descriptor related functions.    Copyright (C) 2019-2026 Free Software Foundation, Inc.    This file is part of the libiberty library.    This program 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 of the License, or   (at your option) any later version.    This program 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 this program; if not, write to the Free Software   Foundation, Inc., 51 Franklin Street - Fifth Floor,   Boston, MA 02110-1301, USA.  */ #include "config.h"#include "ansidecl.h"#include "libiberty.h" #ifdef HAVE_FCNTL_H#include <fcntl.h>#endif #if defined (_WIN32)#define WIN32_LEAN_AND_MEAN#include <windows.h> /* for GetFullPathName */#endif/* Return true when FD file descriptor exists.  */ intis_valid_fd (int fd){#if defined(_WIN32)  HANDLE h = (HANDLE) _get_osfhandle (fd);  return h != (HANDLE) -1;#elif defined(F_GETFD)  return fcntl (fd, F_GETFD) >= 0;#else  return dup2 (fd, fd) < 0;#endif}