_NFILE

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
  1. int _NFILE;
  2. int _NFILE;
  3. int _NFILE;
    version(!Win32 && !linux && !darwin && !FreeBSD && solaris && !X86_64)
    extern (C) const
    int _NFILE;

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