Kernel/Syscalls/dup2.cpp


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/*
 * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include <Kernel/FileSystem/FileDescription.h>
#include <Kernel/Process.h>

namespace Kernel {

KResultOr<int> Process::sys$dup2(int old_fd, int new_fd)
{
    REQUIRE_PROMISE(stdio);
    auto description = file_description(old_fd);
    if (!description)
        return EBADF;
    if (old_fd == new_fd)
        return 0;
    if (new_fd < 0 || new_fd >= m_max_open_file_descriptors)
        return EINVAL;
    m_fds[new_fd].set(*description);
    return new_fd;
}

}